Find a Security Clearance Job!

Military

 

Chapter 10

Marine Emergencies

Fire, sinking, or injuries are constant dangers faced by crew members aboard ships at sea. The organization, training, and teamwork of the crew usually determine the difference between a marine emergency and a marine disaster. The emergency training that is given to the crew is the direct responsibility of the ship's master. This responsibility is the same for the coxswain on the LCM-8 as it is for the master of a category A-2 vessel. This chapter discusses the "how" and "what to do" during a shipboard emergency. Learn now--not during the emergency. Teamwork is essential for survival.

STATION BILL

10-1. The starting point for shipboard survival and survival training is the station bill. The station bill is a muster list that is required by federal regulations. It lists the emergency duty station and duty position for each crew member assigned aboard ship and also the signals for fire and abandon ship.

10-2. The station bill is prepared and signed by the ship's master. Each time a new master is assigned to the ship, one of his first responsibilities is to prepare a new station bill. When a new crew member is assigned aboard ship, the crew member will be assigned to a specific line and station bill number. When transferred, the crew member's name is removed from the station bill.

10-3. The ship's master is the only one who can sign the station bill. It is also his responsibility to keep it current. Copies of the station bill are posted in conspicuous places in the ship, such as the crew's quarters, crew's mess, and bridge.
FILLING IN A STATION BILL
10-4. The following information should be included on a station bill (see also Figure 10-1):
    1. Vessel's name or number.
    2. Date station bill was filled out.
    3. "US Army" or "Name of company".
    4. Master's signature.
    5. A numerical listing for each man authorized aboard the vessel. The Master is listed as A, the Chief Mate is number one.
    6. Crew rating and crew member's name. The crew rating is listed according to precedence in rating and department. If carried, the sequence for departments is deck, engine, radio, stewards, and medical.
    7. Location and specific emergency duty to be performed by crew member.
    8. Specific lifeboat assigned to crew member.
    9. Specific location and task to be performed by crew member.
STATION BILL CARD
10-5. The crew member will also be issued an individual station bill card. This is usually posted next to the crew member's bunk. The card will list the crew member's station bill number, name and rating, fire and emergency station, lifeboat number, abandon ship, and boat station.
ASSIGNING EMERGENCY DUTIES
10-6. The emergency duties assigned to a particular crewman should, whenever possible, be similar to the normal work activity of that person. For instance, steward's department personnel should be assigned to assist passengers; deck department personnel should be assigned to run out hoses and lifeboats; and the engineering department should be assigned to run out hoses in the machinery space with which they are most familiar.

EMERGENCY SIGNALS

10-7. The signal for FIRE is a continuous blast on the ship's whistle or horn for not less than 10 seconds, supplemented by the continuous ringing of the general alarm bells for not less than 10 seconds.

10-8. The signal for ABANDON SHIP is more than six short blasts followed by one long blast on the ship's whistle supplemented by the same signal on the general alarm bells.

10-9. DISMISSAL from fire and emergency stations is signaled by three short blasts on the whistle or ship's horn supplemented by the same signal on the general alarm bells.

10-10. For man overboard, hail the bridge and pass the word "MAN OVERBOARD--PORT or STARBOARD SIDE."

10-11. Emergency signals, other than for FIRE and ABANDON SHIP will be determined by the ship's master. A special signal should be designated by the master to assemble the emergency squad. This signal should be one that will not be confused with the general alarm and navigational signals. Use coded signals to summon the emergency squad, so not to alarm passengers.

 


Figure 10-1. Sample of a Station Bill

 

EMERGENCY SQUAD

10-12. An emergency squad is a group of crew members selected by the master for their special training to deal with emergencies. The chief mate (assisted by the boatswain) is normally in command of the emergency squad. The rest of the squad should be made up of crewmen trained in the use of fire, emergency, and rescue equipment. Candidates for the emergency squad would be crew members who are highly knowledgeable in emergency procedures. A mustering location for the emergency squad should be included in the station bill. The mustering location could be on either wing of the bridge, at a designated position on the main deck, or wherever the master feels would be best. However, the chosen location should be one that the members of the squads can reach promptly--for example, in less than 2 minutes.
TRAINING
10-13. An emergency squad is a team. A team is a group of people brought together to accomplish a common goal. The word team brings to mind word coordination, cooperation, and training. Training is absolutely essential, since without it there can be little coordination or cooperation. Training consists basically of two parts and must be taught in the following order:
  • A teaching-learning process in which the necessary knowledge is communicated to the trainee.
  • Practice and demonstration of the necessary skills, using the proper equipment. As an example, fire drills are practice and demonstration sessions. They must come after crewmen have learned what to do; otherwise, they can serve no purpose except to reinforce bad habits.
10-14. Under an able and understanding leader, proper training will gradually produce coordination and cooperation among members of the emergency squad. After several practice sessions they will be operating as a team.

10-15. The master is responsible for all ship's functions, including those he assigns to subordinates. Although the master assigns the training of the emergency squad (and the rest of the crew) to his chief mate, he should review and approve the plans for proposed lessons and drills. These sessions are made more meaningful when the master personally observes them and then discusses them with those in charge.

10-16. The members of the emergency squad should attend periodic instructional sessions dealing with the variety of emergencies that could occur aboard ship. At each session, a problem could be presented, solutions discussed (until a satisfactory one is found), and the necessary tools and equipment should be handled for familiarity. Then the regularly scheduled fire drills would be demonstrations of efficiency rather than training sessions.
CREW FIRE FIGHTING TRAINING
10-17. The emergency squad may be called upon to deal with many emergencies, such as collision, man overboard, and a lost or damaged rudder. When the fire signal is sounded, all hands are involved. The station bill lists an assigned task and station for each member of the crew. Therefore, all crew members should receive some training in fire fighting.

ABANDON SHIP PROCEDURES

10-18. During all shipboard drills and emergency operations, crew members must wear their life jackets. It is one of the most important pieces of equipment for your survival in the water. It will hold you in the upright floating position without your having to swim. Another safety point during a drill or the real thing is to always wear a hat or some type of headgear to protect you from the elements.
DONNING THE LIFE JACKET
10-19. If you have time, put on extra clothing. Include an outer layer of wind and waterproof clothing fitted if possible with headcover and gloves. Then put on the life jacket in the following manner (see also Figure 10-2):
  • Check the white tag on the lower back of the life jacket. This is the inside, and is worn next to your body.
  • Put your arms through the holes.
  • Pull the jacket up and around your shoulders.
  • Put the neck straps through the D rings on each side of the jacket and tie them in a bowknot.
  • Pull the chest strap and the waist straps tight, and then tie with bowknots.
  • Take the slack out of the belly strap and snap it together.
  • Reach down and back between your legs and grab the left-leg strap and pull it up between your legs.
  • Put the end through the D rings and pull tight.
  • Repeat the procedure for the right-leg straps.
Note: Practice putting on and securing your life jacket until you are able to don and secure it within 2 minutes.

 


Figure 10-2. Donning Life Jacket

 

ENTERING WATER FROM A HEIGHT WEARING A LIFE JACKET
10-20. Make sure that your jacket is well secured. If it is not well secured, you could hurt your head when you jump. Then get down to a height of less than 30 feet if you can. Below 15 feet is ideal. If you jump from higher than 30 feet, you can hurt yourself (this depends on the height from which you jump and the angle at which your body hits the water). If worn, remove false teeth, eyeglasses, or contact lenses. Also remove any sharp objects from your pockets. Get in the jump position (see Figure 10-3) and do the following:
  • Stand on the gunwale and check the water for debris.
  • Check to see if the life jacket is tied and all the straps are secured.
  • Hold your nose and cover your mouth with your left hand.
  • Cross over your left hand with your right hand and hold the life jacket collar securely.
  • Hold your elbows into your side as much as possible.
  • Keep head and eyes straight ahead. Do not look down.
  • Take one step out using either foot.
  • Bring your trailing leg up behind your leading leg so that they cross at the ankles. This will protect you if you should land on any floating debris.

 


Figure 10-3. Jumping in Water

 

10-21. Get away from the ship once you are in the water. Swim as slowly as possible toward the survival craft. DO NOT swim or thrash about any more than you need to because of the following:
  • You will lose your body heat.
  • You will lose your strength. You will need all your strength to pull yourself up and into the survival craft.
  • You should let your life jacket support you in the face-up position.
DROWNPROOFING
10-22. Drownproofing, also called water survival, is based on the natural buoyancy of the human body when the lungs are filled with air. It is intended to keep anyone alive in the water indefinitely, even a nonswimmer who is fully clothed. Drownproofing saves energy for the potential drowning victim. It is much easier to do the steps on drownproofing for long periods of time than to stay afloat by swimming. Each crew member should know drownproofing since it is an excellent way to stay afloat without a life preserver. This method can best be described in the following five steps.
  • Step 1--Resting Position. The swimmer takes a deep breath and then sinks below the surface. The face is kept down with the back of the head even with the water surface (Figure 10-4). In this position, he will sink no deeper.
  • Step 2--Preparing to Exhale. When ready for another breath (in about 6 to 10 seconds), maintaining the body and head position as shown in Figure 10-5, the swimmer slowly lifts the arms to about shoulder height. The legs slowly separate into a scissors-type kick.
  • Step 3--Exhalation. The head of the swimmer is raised just high enough for the mouth to be out of the water (Figure 10-6). The swimmer now exhales through the nose, the mouth, or both. To give the swimmer bearing, the eyes should be open.
  • Step 4 --Inhalation. As the head becomes vertical, the swimmer presses his arms downward and brings his legs together (Figure 10-7). The air is then inhaled through the mouth. The action of arms and legs should be done slowly.
  • Step 5--Return to Rest Position. The swimmer relaxes his arms, and at the same time his legs move back to a dangling position. The swimmer's face goes back into the water and he "rests" once again (Figure 10-8). The cycle is then repeated.
While most persons can master drownproofing easily, skill is involved in breathing close to the water and instruction is necessary.

Figure 10-4. Resting Position


Figure 10-5. Preparing to Exhale


Figure 10-6. Exhalation


Figure 10-7. Inhalation


Figure 10-8. Return to Rest Position

 

TRAVEL STROKE
10-23. This stroke is used in a water survival situation when you are required to swim, while conserving as much energy as possible. Here is how it is done:
  • Enter the water.
  • Take a deep breath.
  • Put your face in the water, arms at your side, feet together, and body horizontal.
  • Prepare to breathe; move your hands up alongside of your body to a position in front of your forehead and palms down. At the same time, spread your legs in scissors fashion in preparation for a kick.
  • Kick and exhale. Bring your feet together quickly and exhale through your nose and mouth. Raise your head slowly out of the water.
  • Stroke and inhale. Stroke a heart-shaped stroke with your hands, then bring your hands back in front of your chest; at the same time, inhale through your mouth.
  • Put your head back in the water and spread your legs for another kick.
  • Kick and level. Extend your hands out in front and at the same time kick, bringing your feet together.
  • Stroke and glide. With your elbows locked, sweep your hands to the side.
  • Continue the glide until your feet start to drop or another breath is required.
  • Repeat the process.
SWIMMING THROUGH THICK OIL FIRE
10-24. The most important thing to remember for your survival if you are forced to swim through a thick oil fire is to keep calm. The proper procedure for swimming through a thick oil fire is described in the following steps:

WARNING: NEVER WEAR A LIFE JACKET WHILE SWIMMING IN A THICK OIL FIRE.
  • Step 1. Enter the water on the windward side of the vessel (windward is the direction from which the wind blows), feet first with one hand over the nose and mouth and the other hand covering the eyes.
  • Step 2. Level out under the surface of the water and start swimming.
  • Step 3. When you must breathe, surface in a straight up-and-down position with your hands extended above your head (Figure 10-9).
  • Step 4. Exhale about 75 percent of the air in your lungs before breaking the surface.
  • Step 5. As soon as your hands break the surface, start beating away the burning oil with a circular thrashing motion.
  • Step 6. Fully inhale before submerging (Figure 10-10).
  • Step 7. Continue swimming in this manner until you are clear of the burning oil (Figure 10-11).

Figure 10-9. Break the Surface


Figure 10-10. Fully Inhale


Figure 10-11. Swimming Through Thick Oil Fire

 

SWIMMING THROUGH A THIN OIL FIRE
10-25. The most important thing to remember for your survival if you are forced to swim through a thin oil fire is to keep calm. The proper procedure is shown in Figure 10-12, and described in the following steps:

WARNING: WEAR YOUR LIFE JACKET AT ALL TIMES WHILE SWIMMING THROUGH A GASOLINE OR THIN OIL FIRE. KEEP YOUR HEAD ABOVE WATER AT ALL TIMES.
  • Step 1. Enter the water from the windward side of the vessel, feet first with one hand over the nose and mouth and the other hand covering the eyes.
  • Step 2. Bring your hands up in front of your face, elbows extended with the palms halfway out of the water.
  • Step 3. Push the water out in front and continue the stroke until your arms are straight out from the body.
  • Step 4. Continue swimming until you are out of danger.

 


Figure 10-12. Swimming Through Thin Oil Fire

 

COLD WATER DROWNING
10-26. After reading the following, you and your crew, as would-be rescuers, should be more willing to attempt to revive a person who is supposedly "drowned."

10-27. Due to recent medical research, it has been discovered that the bodies of people "drowned" in cold water (below 70° F, 21° C) may go into a diving reflex. In this condition, the nervous system cuts off the flow of blood to all parts of the body except the brain and lungs. The heart slows so much that it cannot be heard without special instruments. The result is that a person can exist in seemingly a "dead" state for up to an hour, depending on the their age and the temperature of the water. The basic trigger that starts the diving reflex is cold water touching the face, specifically the area around the eyes and forehead.

10-28. However, the diving reflex does not always work. Studies show that the person's age combined with the temperature of the water are the main factors in deciding whether the reflex will start, and, if so, how long it will be effective. Its effectiveness is measured by how long it works before permanent brain damage begins.

10-29. The reflex is extremely active in youngsters. In infants and small children, it can be started by a water temperature of 65° F (18°C) and can, in theory, last for as long as an hour. As a person gets older, the water must be colder to start it and it is effective for a shorter time. The diving reflex may be one of those natural systems, which protects small children from their own inexperience.

10-30. A person's body weight also comes into play when the reflex is connected with hypothermia. Hypothermia simply means that the body temperature is below normal. However, when you take your temperature and it is 97.5°F instead of 98.6° F, it does not necessarily mean that you are a hypothermia victim. Hypothermia usually refers to the lowering of inside body temperature because of coldness outside the body such as cold water or a cold wind. Your arms and legs will become numb and you will lose the use of them if your body temperature gets down to about 93oF. When it reaches 80° to 86°F, you may lose consciousness; should it drop to about 79°to 77°F, it becomes fatal.

10-31. A person's weight is a factor when figuring how long it will take for all this to happen. Generally, the bigger a person is, the longer it takes for his body to lose heat because he has better insulation. Other factors that affect this heat loss are age, clothing, and physical activity.

10-32. It is the result of cold rather than the effect of drowning that begins the diving reflex. Hypothermia victims, even those not in cold water, often get some assistance from the reflex. In reaction to the cold, the vital body functions slow down to an almost unmeasurable level and thereby save body heat as well as oxygen. Again, this lengthens the time before serious brain damage begins. This extension can make the difference between whether or not a "drowned" person, or hypothermia victim, can be successfully rescued.

10-33. Tests during World War II revealed that a thin person in a flight suit and life jacket could survive up to 72 minutes in 40° F (5°C) water. However, he would be unconscious and apparently dead some time before that.

10-34. While this knowledge of the diving reflex may be consoling to a person drowning and going down for the final time, it is primarily important to his rescuers. Should your vessel be the first one on the scene of a cold water drowning, the things you and your crew do can determine whether the victim lives or dies.

10-35. Since you can never assume that medical assistance will be on the scene when a drowning victim is pulled from the water, his life may depend on you. The diving reflex stops as soon as the victim is taken out of the water. That means that you may have less than 4 minutes to get his blood flowing. Table 10-1, shows some DOs and DO NOTs to remember when reviving cold water drowning victims.

Table 10-1. Reviving Cold Weather Drowning Victims

DO

DO NOT

Start CPR immediately. This is a form of mouth-to-mouth resus-citation and external heart massage. Only a person that is qualified should attempt CPR. Check with your installation's hospital about available CPR training programs.
Keep the victim warm with a light blanket or jacket, and so on, but do not waste necessary time on this.
Keep giving CPR until medical assistants take over or until the victim revives.
Give the victim any alcoholic drink.
Try to rewarm the victim with anything more than a light blanket, jacket, or so forth. Uncontrolled rewarming can cause severe injury.

FIRST AID FOR COLD WATER VICTIMS
10-36. Treatment will depend on the condition of the survivor and the facilities available. In more serious cases, where the victim is semiconscious or unconscious, contact should be made immediately with a ship or shore medical facility for detailed information on the care and handling of the victim. Administer the following first aid while waiting for medical instructions:
  • After removing the victim from the cold water, gently transfer him to a warm environment. Rough handling of the victim can cause further harm.
  • Remove his clothes only if it can be done with a minimum of movement of the victim's body. Do not massage him.
  • Lay the victim in a face up and slightly head down position, unless vomiting occurs. This is important because a hypothermia victim has low blood pressure, and the head-down position ensures an adequate supply of blood to the brain.
  • If available, administer warm, humidified oxygen by means of a face mask. The oxygen will not only assist victims if they are having difficulty breathing or have a low respiratory rate, but it will also provide core rewarming. Mouth-to-mouth resuscitation is always advisable if the victim is having problems breathing and no other form of assistance is available.
10-37. In some cases, you should rewarm the victim actively; in other cases, you should not rewarm him at all. Before deciding what to do, you need to know something about the following two different types of hypothermia.
Chronic, or Slow Onset Hypothermia
10-38. This type comes from being exposed (from a few hours to several days) to cold weather. Most chronic hypothermia cases develop in air temperatures of 30° to 50° F. The victim usually overestimates how long he can withstand the cold and fails to recognize the danger of being wet at such temperatures. A victim can get wet from sweat, rain, or from the splash and spray of water from working on the deck of a vessel. Because chronic hypothermia takes some time to develop, the victim may undergo dangerous fluid and biochemical changes. For these reasons, you do not want to rewarm the victim. As with a cold water drowning victim, victims of chronic hypothermia should be taken to a hospital as quickly as possible. REMEMBER, DO NOT REWARM A CHRONIC HYPOTHERMIA VICTIM!
Acute, or Rapid Onset Hypothermia
10-39. This type of hypothermia is different and is the result of immersion in cold water. Since water can withdraw heat from the body 25 or more times faster than air, we can estimate that in water temperatures of, 72°F and lower, the body cannot generate enough heat to offset heat loss to the water. Depending on water temperatures and body condition, acute hypothermia may begin to develop in as little as 10 to 15 minutes. Because of the rapid onset, acute hypothermia victims do not generally have time to develop dangerous chemical and fluid imbalances. Therefore, without delay, begin to REWARM ACUTE HYPOTHERMIA VICTIMS IMMEDIATELY. Even conscious hypothermia victims have died following apparently successful rescues when attempts at rewarming were delayed or were inadequate. Any of the following warming methods are recommended, preferably in the order given.
  • Place the survivor in a hot shower or bath at 105° to 110°F or a temperature in which an observer can comfortably leave his arm. Keep the arms and legs out of the bath. If you are warming a victim in a shower, keep his limbs out of the spray to delay the return of blood circulation to the extremities since heating the limbs causes cold blood to flow from them to the body core. This further cools the core. Rather, direct the spray on the center of the back or the chest.
  • Apply hot, wet towels or blankets at 115° F to the victim's head, neck, groin, chest, and abdomen. Again, do not attempt to warm his arms and legs.
  • Apply your own body warmth by direct body-to-body contact with the victim. A blanket should then be wrapped around you and the victim to conserve the heat you are supplying. Unless he is in a warm environment, just wrapping a hypothermia victim in a blanket without a heat source is ineffective. This is because he is not generating sufficient heat to rewarm himself and the blanket insulates him from the warm environment.
10-40. Let us clear up something that may be confusing about rewarming cold water survival and drowning victims. Suppose a person has been in cold water (below 70°F) and was recovered within a 10- to 15-minute time span. Would you start first aid treatment as a chronic or acute hypothermia victim? You would treat this victim as a chronic hypothermia patient--you would not rewarm him. As in chronic hypothermia, the body could undergo dangerous biochemical changes.
COLD WATER SURVIVAL
10-41. The following will teach you how to improve your chances of survival in cold water. As mentioned before, body heat loss is a gradual process and the diving reflex provides some protection.

10-42. The loss of body heat is probably the greatest hazard to the survival of a person in cold water. Knowing what steps to take to help your body delay the damaging effects of cold stress will help you stay alive in the event of cold water exposure. Try protecting your head, neck, groin, and the sides of your chest. These are areas of rapid heat loss in cold water.

10-43. Locate and wear personal flotation equipment such as a life jacket. If you are not wearing it when you enter the water, put it on as soon as possible after entering the water. This is probably the single most important item of survival equipment. Survival in cold water is tough enough without having to contend with staying afloat. Learn how the flotation device is worn and used before an accident occurs.

10-44. Try to enter the water in a lifeboat or raft. This will avoid getting your insulation wet and lost of valuable body heat to the water. Abandoning a ship by means of a lifeboat or raft will greatly increase the chance for survival. This is better than jumping overboard and attempting to be rescued.

10-45. Wear several layers of clothing. If you are fortunate enough to stay dry and enter the water in a lifeboat or raft, the trapped air within your layers of clothing will provide excellent insulation. However, if you become wet in abandoning your ship, the layers of clothing, although wet, will slow down the rate of body heat loss.

10-46. If conditions prevent you from abandoning ship in a lifeboat and you must enter the water directly, try to cut down the shock of a sudden cold plunge in the water. Rather than jumping into the cold water, try to lower yourself gradually. A sudden plunge into cold water can cause rapid death as a result of the severe shock to your nervous system. It may also cause an uncontrollable rise in breathing rate resulting in an intake of water into the lungs. If jumping is necessary, try to hold your breath, pinch your nose, and avoid swallowing water during the plunge.

10-47. The body position you assume in the water is very important in conserving your body heat. Tests show that the best body position is one where you hold your knees up to your chest in a "doubled up" fashion with your arms tight against the side of your chest (Figure 10-13). This position reduces the exposure to the cold water of your groin and chest sides, both areas of high heat loss. Try to keep your head and neck out of the water.

10-48. Another heat conserving position is to huddle closely to one or two others afloat, making as much body contact as possible (Figure 10-14). You must be wearing a life jacket to be able to hold these positions in the water. You should also wear a life jacket in the lifeboat or life raft.


Figure 10-13. Double-up


Figure 10-14. Buddy-up

10-49. Try to board a lifeboat, raft, or other floating platforms or objects, as soon as possible, in order to shorten immersion time. Remember that you lose body heat about 25 times faster in water than you do in air. Since the effectiveness of your insulation has been seriously reduced by water soaking, you must now try to shield yourself from wind to avoid a wind-chill effect (convective cooling). If you manage to climb aboard a lifeboat, shielding can be accomplished with the aid of a canvas cover, a tarpaulin, or an unused garment. Huddling close to the other occupants of the lifeboat or raft will also conserve body heat.

10-50. Keep a positive attitude about your survival and rescue. This will improve your chances of extending your survival time until you are rescued.
MAN OVERBOARD PROCEDURES
10-51. Immediately on seeing a crew member fall over the side, shout an alarm! Call out the words "Man overboard!" to personnel on the bridge. Be sure to include where on the vessel the person fell overboard. For example:
  • On the right side of the vessel call out: "Man overboard, starboard side!"
  • On the left side it would be: "Man overboard, port side,"
  • At the front of the vessel it would be: "Man overboard at the bow!"
  • At the rear it would be: "Man overboard at the stern!"
Action
10-52. Immediately after these vocal alarms are given, three things must happen at the same time:
  • Get the stern away from the victim.
  • Mark the spot.
  • Post a lookout.
10-53. These things do not happen 1-2-3; they are done at the same time. That is why teamwork is a necessity. The first action of the person in charge of the vessel is to get the stern away from the victim. On a small craft it may be necessary to cut the throttle immediately and swing the stern away from the person in the water to avoid hitting him with the screws.

10-54. When the bridge watch hears the man overboard signal, the helmsman must be told immediately to put the rudder hard over to swing the stern away from the victim. If the victim falls overboard on the starboard side, the helmsman would turn the helm "hard right rudder." If the victim falls over on the port side, then naturally the helm will be put to "hard left rudder."
Mark the Spot
10-55. There are two procedures for marking the spot. One is used during hours of daylight the other is for hours of darkness. To mark the spot during daylight:
  • Throw a life preserver or life ring immediately.
  • Drop a smoke float.
  • Get anything that floats into the water near the person that he can hang onto.
To mark the spot during darkness:
  • Immediately throw a life preserver or buoy ring with water lights.
  • Keep the vessel's searchlight trained on the victim.
Post a Lookout
10-56. Keep the victim in sight. It is easy to lose sight of the victim's position, especially in rough weather or at night. The person who saw the victim fall overboard usually makes the best lookout. It is also a good idea for the lookout to be posted on the forward part of the vessel for easier viewing.
Raise the Oscar Flag
10-57. The Oscar Flag is raised to let other vessels in the area know that you have a man overboard.
Pick up the Victim
10-58. If circumstances permit (such as if you are not limited by narrow channels or landfalls, and so forth), the Williamson turn, used by large vessels, has proven to be the preferred maneuver for picking up victims (Figure 10-15). To make the turn you must do the following:
  • Put the rudder over to the side from which the victim fell. This action swings the stern away from that person.
  • Hold the rudder hard over until the vessel begins to turn.
  • Then steady her on a course about 60° off the original course.
  • When the vessel heads on the new course, turn the rudder hard over to the opposite side until she is on a course 180° from the original course.
  • Maintain the original speed until the vessel is steady on the reverse course.

 


Figure 10-15. Williamson Turn

 

Other Maneuvers
10-59. On large vessels equipped with lifeboats, a lifeboat is lowered and the lifeboat crew maneuvers into position to rescue the victim. A small vessel, especially one with two screws, often is so maneuverable that it is simpler, safer, and quicker to maneuver the vessel back to the person in the water and throw them a line than to make the Williamson turn. For example, an LCM or LCU could make the pickup at the ramp. The vessel must turn around until its course has been reversed. At slow ahead, when it has been determined that the propellers will not endanger the person in the water, the vessel can be maneuvered toward them.

10-60. The vessel must approach slowly on the windward side of the victim. If the vessel is placed so that it shields the victim from the waves and the wind, the water around the victim will be calm. However, caution must be exercised to prevent the vessel from coming too close to the victim (Figure 10-16). Lines with life rings must be prepared so they can be thrown as soon as possible. The only time maneuvers of this type may be used at night are when weather conditions make launching a boat impossible.

10-61. When having man overboard drills, it is a good idea to identify all crew members who are good swimmers, and designate them for special emergency duty. When an overboard victim is unconscious, a good swimmer with life preservers and lifelines can jump in and help with the rescue. The first thing a man overboard should try to do is to get clear of the vessel, especially the stern, so that he does not get sucked under or hit by the screw.

 


Figure 10-16. Bringing Ship Into Wind

 

10-62. The overboard victim should stay in the same general area where he fell, especially at night and in foul weather. Staying in the same general area will make it easier for the ship's lookouts to spot him since they will generally know where to look.

10-63. Victims of a fall overboard can help the ship's lookouts by:
  • Making themselves more visible.
  • Making themselves heard.
A victim can help to make himself more visible by waving his arms, a handkerchief, his T-shirt (if the water is not too cold) or any brightly colored object he might have been holding or wearing when he went overboard. If he was wearing a life preserver when he fell, and he does not need it to stay afloat, he can float the preserver alongside himself in the water. However, if the water is rough or if he is a poor swimmer, he should NEVER remove his preserver.

10-64. A victim can make themselves heard by the following:
  • Shouting (if in hearing distance).
  • Splashing the water (which can also improve his visibility).
  • Sounding the whistle (if he was wearing a life preserver when he fell overboard).
10-65. Up to now, we have covered what to do if an overboard accident happens. Let us go over the different kinds of man overboard accidents, what causes them, and the things we can do to prevent them.

10-66. Most falls happen while a person is moving, standing, or leaning over the edge of a vessel. However, falls may occur from a wide range of causes which include, but are not limited to the following:
  • Limited visibility caused by darkness, fog, or bad weather.
  • A sharp turn or acceleration.
  • A wave or wake striking the vessel.
  • Sitting on a gunwale, the stern, or the bow.
  • A slippery surface.
10-67. The following are some things you can do to prevent an overboard accident:
  • Do not allow horseplay.
  • Make sure everyone uses the handrails.
  • Have everyone watch where he walks to avoid tripping.
  • Make sure lifelines are rigged for crew members to use when working near the edge of the vessel.
  • Do not allow anyone to sit on gunwales.

LIFE RAFTS

10-68. The inflatable life raft is as important a lifesaving device as the lifeboat. Shipboard drills with the inflatable life raft are not conducted because the raft container is sealed until ready for automatic or manual launching. Therefore, it is important to learn about the current design of rafts and keep informed of future design.
LIFE RAFT SIZE
10-69. Inflatable life rafts must be either Navy standard or Coast Guard approved. Life rafts have a range of sizes. Ships that do not make international voyages might have rafts that can hold 4 to 26 people. Ships that make international voyages might have rafts that can hold 6 to 25 people. The capacity (number of persons it will hold) of the life raft is marked on the container and the raft. The manufacturer's name is also shown on the container. An inflatable life raft (complete with case and equipment) does not weigh more than 400 pounds.
LIFE RAFT STOWAGE
10-70. Life rafts are kept in a cradle on an open deck (Figure 10-17). This is done so they can float free if the ship sinks before you can manually launch the raft.

10-71. The life raft container is strong, weathertight, and tamperproof. The raft container has small holes on the bottom for condensation drainage and air circulation. The container must be stowed with the words "THIS SIDE UP" on top to be sure the holes are on the bottom. Most containers are made of fiberglass.

10-72. The raft container is usually held together with packing bands, which break when the raft is inflated. A watertight gasket seals the two halves of the container together.

10-73. The container rests in a cradle. The cradle is permanently secured to the ship's deck. The container may be secured to the cradle with tiedown straps. A tiedown strap has a securing device called a hydrostatic release. A cleat provided near the cradle is used for tying the operating cord when launching manually.

 


Figure 10-17. A Cradled Life Raft

 

LIFE RAFT DESIGN
10-74. Buoyancy tubes are located on the outer edge of the raft. They are made of thick nylon-reinforced rubber. The buoyancy tubes make the raft float. They are divided into at least two compartments. The raft is made to support its rated number of persons even if half the compartments in the buoyancy tubes are deflated.

Note: Inflatable life rafts may be designed to be round, oval, octagonal (eight-sided) or boat-shaped. Specific design may vary among manufacturers. A typical oval inflated life raft is shown in Figure 10-18.

10-75. Carbon dioxide is usually used to inflate the raft. The CO2 cylinder (container) is on the bottom of the raft. It is activated by a sharp tug on the 100-foot long operating cord. The tug pulls the CO2 tripping lanyard out of the CO2 to enter the buoyancy tubes. The CO2 can escape through leaks in the tubes. The gas is odorless, tasteless, and colorless, so you must watch for leaks. If you breathe air with a large amount of CO2, you can suffocate, so always leave the curtains open if you know the tubes are leaking. Fix the leak as soon as possible.

 


Figure 10-18. A Typical Oval Inflated Life Raft

 

10-76. Pressure relief valves are installed in most rafts. These valves are fitted in the tubes, so excess (extra) gas can automatically escape. It is normal for gas to escape right after the raft is inflated. You can tell it is escaping if there is a hissing sound coming from the valve. The sound will probably stop after a few minutes.

10-77. During the day, the rise in temperature might cause the gas to expand enough to activate the valves. At night, when the temperature drops, you may have to pump up the tubes with the inflation pumps because the air in the tubes might contract.

10-78. Sometimes, pressure relief valves do not work correctly. If gas continues to escape from the pressure relief valve, you can fix it with a safety valve plug from the repair kit. Then pump the tube back up. Deflation plugs are provided to deflate the raft after rescue.

10-79. The floor of the raft is also inflatable. In cold climates, the floor should be inflated with the inflating pump. This will insulate the occupants from the cold seawater. The floor should be left deflated in warm climates. This will allow the cooler seawater to cool the inside of the raft. If necessary, some inflatable floors can be removed and used for an extra emergency float.

10-80. A boarding ladder and towing bridle are fitted at each end of the raft. The two are usually combined. In addition to boarding and towing the raft, the raft can be hoisted aboard a ship by hooking onto one or both towing bridles. Lifelines are provided inside and outside the raft for survivors to steady themselves.

10-81. Two lights are installed on the canopy. These lights are automatically activated when the raft inflates. They are powered by either dry cells or water-activated batteries. The lights can operate for at least 12 hours. The external recognition light can be seen from 2 miles away. The other light is inside the canopy. Unscrewing the bulbs during the day will prolong battery life.

10-82. The canopy has two layers to insulate the inside from extreme temperatures. It erects (pops up) automatically as the arch tubes inflate. The canopy has tubes to collect rainwater. The canopy is colored Indian orange or some other bright color, which would stand out on a whitecapped sea.

10-83. Water pockets are located under the floor. They have holes in them to allow seawater to fill them up when the raft is launched. Water pockets have two purposes: to slow the drifting of the raft and to make the raft more stable (less likely to capsize).

10-84. The early designs of water pockets were simple, but did not always work well. In heavy seas or high winds, an empty or unevenly loaded raft with three or four small water pockets could easily capsize. Some inflatable life raft manufacturers have improved the basic stabilization design.

10-85. The Givens raft has a large stability chamber instead of the small water pockets. As the angle of the sea changes, the stability chamber adjusts the raft's center of gravity to compensate for the wave action. When the Givens raft reaches the crest of a wave, the raft bottom should not lose contact with the water, and should not be caught by the wind and capsize. The raft is not easily capsized in high winds with its minimum of 4,800 pounds of water ballast (on the four- to six-person raft). The stability chamber can be deballasted (emptied) so the raft can be towed.
MANUALLY LAUNCHING A LIFE RAFT
10-86. You are required to know how to manually launch a life raft. Do the following steps to successfully perform this task:
  • Step 1. Pull open the hook at the hydrostatic release to release the tiedown straps.
  • Step 2. Secure the operating cord (painter/lanyard) to the cleat. Make sure that the operating cord is free of tangles.
  • Step 3. DO NOT REMOVE the bands around the container. They will automatically break open when the operating cord is pulled.
  • Step 4. With two or more crew members, throw the life raft in its container overboard (Figure 10-19).
  • Step 5. With the life raft and container in the water, pull on the operating cord (Figure 10-20). The bands on the container will break and the life raft will automatically inflate.
  • Step 6. Leave the operating cord attached to the cleat aboard the ship.
  • Step 7. Board the life raft as soon as possible (Figure 10-21).
  • Step 8. Remove the knife from the pocket on the canopy.
  • Step 9. Cut the operating cord to free the life raft from the sinking ship.
  • Step 10. Read the survival manuals that are found inside the raft. These will give you complete instructions on what to do while you are in the life raft.

Figure 10-19. Throwing in Life Raft


Figure 10-20. Yanking on the Operating Cord


Figure 10-21. Boarding Life Raft

 

AUTOMATIC LAUNCHING OPERATION
10-87. After the ship sinks to a depth of 10 to 15 feet, the hydrostatic release will automatically release and free the life raft container. The container will rise to the surface (Figure 10-22). The pull of the sinking ship will cause the container bands to part and trigger the inflation of the life raft. The life raft will be completely inflated and ready for boarding within 30 seconds. The buoyancy of the life raft will cause the operating cord to part (Figure 10-23).


Figure 10-22. Containers Rises to Surface


Figure 10-23. Operating Cord Parting

GETTING ABOARD THE LIFE RAFT
10-88. The life raft may be boarded by any one of these procedures:
  • By climbing down a ladder.
  • By jumping into the canopy (Figure 10-24).
  • By entering from the ship or from the sea (Figure 10-25).
If you can, stay dry when getting off a vessel. Sometimes this is possible by climbing down a ladder, net, or line until you are within 4 feet of the raft. Then jump into the open canopy entrance. Land on the floor of the raft with the balls of your feet. (If you land with your heels first, you could fall backwards into the water.) Stretch out your arms and land with your chest against the inflated canopy arch. DO NOT jump onto the roof of the raft! People inside could be injured. 10-89. When boarding from the sea, place your feet on the boarding ladder. Reach inside the raft and grab the internal lifelines (if there are no external handholds provided). Pull yourself into the raft headfirst. Do not grab hold of the canopy to pull yourself because it tears easily.


Figure 10-24. Jumping Into Canopy Opening


Figure 10-25. Boarding a Life Raft From the Sea

10-90. Two people can help an injured person board an inflatable life raft as shown in Figure 10-26 and doing the following:
  • Place their outboard knees on the top of the buoyancy tube.
  • Turn the injured person with his back toward them.
  • Grab the injured person's life jacket with their inboard hands.
  • With their outboard hands, grab the injured person's upper arms.
  • Push the injured person slightly down into the water and, using his buoyancy to help them, spring him up and over into the life raft, back first.
  • The two rescuers fall to either side on the raft's floor. This allows the injured person to fall between them.

 


Figure 10-26. Bringing Aboard an Injured Crewman

 

LIFE RAFT SURVIVAL EQUIPMENT

10-91. Inflatable life rafts are provided with equipment necessary for handling the life raft, surviving at sea, and alerting rescuers. The following list is for inflatable life rafts on ocean service ships. Ships on the lakes, bays, sounds, and rivers have considerably less equipment.
  • Heaving Line. A buoyant heaving line, 100 feet long, that has a buoyant quoit (small floating ring) at one end. The other end is attached to the raft near the after entrance.
  • Instruction/Survival Manual. A booklet printed on water-resistant material hanging in a clear envelope from one of the canopy arch tubes. The manual describes how to use the raft's equipment. It also contains internationally recognized distress signals and survival information.
  • Instruction Card. A plastic card hangs from the inside canopy. The card shows immediate steps to be taken by survivors upon entering the raft.
  • Jackknife. One jackknife is provided on rafts holding up to 12 persons. Two are required on larger rafts. The knife has a can opener. One of the knives is in a pocket near the forward entrance. It can be used to cut the painter. If the raft is provided with a floating sheath knife, it can replace the jackknife.
  • Paddles. Two 4-foot long paddles are included.
  • Inflation/Dewatering Pump. A pump is provided so survivors can keep the raft inflated. The pump can also be used to pump water out of the raft by switching the hose.
  • Sea Anchors. Two sea anchors are provided. One sea anchor attaches to the outside of the raft and streams automatically when the raft is inflated. The other one acts as a spare. Each sea anchor has 50 feet of nylon line attached.
  • Bailers. Two flexible bailers are provided on rafts carrying 13 or more people. One bailer is carried on smaller rafts.
  • Sponges. Two cellulose sponges are provided.
  • First Aid Kit. A kit containing first aid supplies is provided.
  • Flashlight. A flashlight with three spare batteries and two spare bulbs is provided. The flashlight is Coast Guard-approved. It is waterproof and has a blinker button for signaling.
  • Signal Mirror and Whistle. A mirror and whistle for signaling rescue units are provided.
  • Red Rocket Parachute Flares. Two red rocket parachute flares are provided. They are approved for 3 years of service.
  • Hand-Held Red Flares. Six hand-held red flares are provided. They are approved for 3 years of service.
  • Provisions. One pound of hard bread or its approved nutritional equivalent is provided for each person. The food is packed in sealed cans.
  • Water. One and one-half quarts of water are provided for each person. The water comes in sealed cans. The cans are approved for 5 years after packing. Some rafts may contain a desalting kit for each person. The contents of the kit can be mixed with saltwater to produce 1 pint of drinking water.
  • Can Openers. Three can openers are provided.
  • Drinking Cup. A flexible drinking cup marked in ounces is provided.
  • Fishing Tackle Kit. A kit containing fishing tackle is provided.
  • Anti-seasickness Tablets. Six anti-seasickness tablets are provided for each person.
  • Repair Kit. A repair kit for repairing the buoyancy tubes is provided. The repair kit contains a roughing tool, five rubber tube patches (2-inch diameter), and cement. The cement is flammable. There must be no smoking while making repairs. The patches are used for patching small holes. Use patches only if the area around the hole can be kept dry while you are repairing the hole. Roughen the surface of the area that needs patching. Apply cement to both the patch and the area around the hole. Be sure the patch is 1 inch larger than the hole. Allow both to dry. Apply a second coat of cement to both. When both are tacky, press the patch on the hole. Do not completely inflate the raft until the patch has had 24 hours to dry.

PATCHING WITH SEALING CLAMPS

10-92. Six sealing clamps are also included in the kit for plugging large holes and any hole which cannot be kept dry enough to use cement. Use the following procedures:
  • Loop the cord on the clamp around your wrist to prevent losing the clamp.
  • Dip the clamp into the water. This makes the clamp slippery, so it can be inserted easily.
  • Push the bottom plate through the hole (see Figure 10-27).
Note: If the hole is too small, carefully enlarge it so the clamp can be forced in.


Figure 10-27. Pushing Bottom Plate Through Hole

  • Pull the bottom clamp against the inner surface of the tube, and slide the top clamp over it (Figure 10-28).
  • Adjust the clamp to completely cover the hole.
  • Hold it in place and screw down the wing nut until it is tight (Figure 10-29).
  • Break off the wire holding the cord.


Figure 10-28. Sliding Top Clamp Over


Figure 10-29. Tightening Wing

SIGNALING

10-93. The importance of a good lookout cannot be overstated. Remember, when in a life raft, you are so small and the sea is so big that it is very easy for a search ship or plane to overlook you. An alert lookout will make the difference in survival. Once you have sighted a rescue ship or aircraft, use the following to attract their attention:
  • Signaling mirrors. Read the instructions for the particular kind of signaling mirror in your survival equipment. Do not wait until you see a rescue craft to use the signaling mirror. When the sun is shining, flash the mirror all around the horizon (Figure 10-30). An aircraft can spot the flash long before you would see the aircraft. The signaling mirror may save your life. Use it as long as the sun is shining.
  • Whistles. In calm weather, your voice can be heard only a few undred yards away. If you keep screaming, you will become hoarse and lose your voice. A whistle, on the other hand, can be heard up to 4 miles away in favorable weather conditions. It can come in handy when you are floating in the water trying to attract the attention of nearby rescuers. A whistle can be used over and over again. It can be used in fog, at night, or during the day.
  • Pyrotechnics. These are signals such as rockets, flares, and smoke. Instructions for operating various brands of pyrotechnics are written by the manufacturers. Once you are settled in your survival craft, read the instructions on each type of pyrotechnic so you will know how to use them when a ship or aircraft is spotted. Keep the pyrotechnics close by for immediate use, so you can signal when necessary. Heed the following when using pyrotechnics:
  • Be sure to fire the signals downwind on the lee side of the survival craft. When firing, hold them at a slight angle over the water. Pyrotechnics have burning particles that might fall, which may burn you or damage the raft.
  • Only use smoke signals during the daytime. Smoke does not glow in the dark. Only use pyrotechnics when you can see a ship or plane. Do not waste smoke signals.
  • Rockets should be used when a vessel is spotted far away on the horizon. A rocket will get the signal higher, where it can be seen from a greater distance.
  • An aircraft directly overhead would be more likely to spot a hand flare than a flare covered with a parachute.
  • Emergency Position Indicating Radio Beacons. Your ship may also have at least one EPIRB. There are different makes of EPIRBs. They all have the following things in common:
  • EPIRBs float. They are stowed on the outside of the ship, so they will float free if the ship sinks.
  • They are small (approximately 6 inches thick and 1 to 3 feet long).
  • They transmit signals automatically on two international distress frequencies for military and civilian aircraft. These frequencies are 121.5 and 243 MHz.
  • Most EPIRBs work on one-way automatic operation only and cannot be used for two-way communication.
  • They transmit a continuous two-tone (hi/lo) signal.
  • EPIRBs are easy to use.
  • If your EPIRB is floated, tie it to the survival craft, so it will not drift away (Figure 10-31).


Figure 10-30. Signaling Mirror


Figure 10-31. EPIRB Secured to a Life Raft

RIGHTING AN OVERTURNED LIFE RAFT

10-94. If a capsized raft can be righted (turned right side up) before the inverted (upside down) canopy fills with seawater, one person can easily right it using the following procedure:
  • Swim to the side marked "RIGHT HERE." If it is not marked, go to the side where the CO2 cylinder is located. Reach up and grab the righting strap. Start pulling yourself up onto the raft. It may help to kick your feet out as if swimming (Figure 10-32). If this does not work, try putting your feet or knees into the external lifelines to help you pull yourself up on the raft. Some rafts may right while you are climbing onto them. Others are more difficult to right.
Note: A righting strap is fitted on the underside of the raft to right the raft if it capsizes or inflates upside down. The righting strap runs the full width of the oval or round raft.
  • Stand on the very edge, where the CO2 cylinder is located. Lean back with all your weight while pulling on the righting strap (Figure 10-33).
If the canopy is clear of water, the raft will begin to follow you. If the raft is large, it will land on your head unless you bend your knees and spring backwards just as the raft begins to free fall (Figure 10-34). This should allow your head to clear the raft.


Figure 10-32. Getting Aboard an Overturned Life Raft


Figure 10-33. Standing On Edge


Figure 10-34. Knees Bent

10-95. Do not panic if the raft does land on top of you. Because the bottom of the raft is soft and flexible, you can create an air pocket by pushing your arms or head against the floor. This will give you a chance to catch a breath of air. Use your arms and swim face up to get out from underneath the raft. If you try to swim out face down, the raft may hang up on the back of your life preserver. If this happens, it will be difficult for you to get out from underneath the raft.

10-96. If one person cannot right a capsized raft, the canopy probably has filled with seawater that cannot escape. Try two persons pulling on the righting strap. If this does not work, then get several persons in the water on the opposite side of the raft (Figure 10-35). These persons should work the water out of the canopy by pushing up on the canopy while two people pull on the righting strap.

10-97. If the inverted canopy fills with seawater, the raft may be more difficult to right. Generally, round rafts have the righting strap parallel to the canopy openings. This allows the water to flow freely out of the raft while the raft is being righted.

10-98. If the raft is oval with the righting straps at right angles to the canopy openings, water tends to stay trapped in the canopy. It may take several persons to right this type of raft.

Note: Figure 10-36, shows the overhead views of round and oval rafts.

10-99. A single person may be able to right a waterlogged raft. He can try by pulling and walking the righting strap through his hands until the opposite side is pulled over. This takes a lot of strength and may be very hard to do. It might be done without climbing aboard the raft.


Figure 10-35. Several People Righting An Overturned Life Raft


Figure 10-36. Overhead Views of Round and Oval Rafts

SURVIVAL ABOARD A LIFE RAFT

10-100. Life rafts are important in a marine emergency. The life raft is the primary means of escape in a shipboard emergency. Survival aboard a life raft starts with the proper launching and inflating of the life raft. Survival can also include how to correctly board the raft, avoiding hypothermia, how to right an upside down life-raft, know how to properly use safety equipment, anchoring the raft, plugging leaks, dealing with seasickness, establishing a chain of command, and rescue.

Preserve Body Fluids--Avoid Seasickness

10-101. Riding in a life raft is very uncomfortable. Your raft will be in constant motion even on a calm sea. A raft wiggles every time someone moves inside or the water moves underneath. You will be confined in a cramped and stuffy space. Even the most experienced seafarers tend to get seasick in a raft. Seasickness must be avoided if at all possible. It is a very miserable illness and can affect your will to survive.

10-102. If on hand, take a seasickness pill (if you can) before you abandon ship. If unable to take, take a seasickness pill found in the raft's supply kit as soon as all of your shipmates have been helped into the raft. The pills will keep you from vomiting. Vomiting empties your stomach of valuable fluids. You must preserve those body fluids. If you lose them, they will be difficult or even impossible to replace as long as you are in the raft. Remember how cramped your survival conditions may be. If one person vomits, others will probably do the same.

TAKE SEASICKNESS PILLS
AS SOON AS YOU CAN!

Urinate Soon After Boarding

10-103. If you did not urinate within a few hours before boarding the survival craft, you should do so within 2 hours. The traumatic effects of a disaster at sea may make urination difficult. You could damage your bladder if you do not pass urine. There are two methods that might help you urinate:
  • Have someone pour seawater slowly back and forth from cup to cup in front of you.
  • Hang over the side with the water waist high. The cool water should help.
After several days with little drinking water, do not be alarmed if your urine appears dark and thick. Such a reaction to dehydration is normal.

Sit on a Life Jacket for Protection

10-104. In moderate seas, when there is no danger of the raft capsizing, you should take off and sit on your life jacket. The rubber raft constantly moving under you tends to wear your skin until soreness occurs. Your life jacket will provide a cushion that will prevent such soreness.

Cover Up

10-105. The dangers from exposure to cold are obvious, BUT do not forget the sun, wind, rain, and sea. The life raft comes with a built-in canopy to protect you. Do not cook yourself in the sun! Serious burns and loss of valuable body fluids could result from a sunburn. Wear light clothing or stay under the cover. 10-106. The following are some hot climate tips:
  • If possible, keep a breeze blowing through the survival craft. Sometimes you can change the position of the sea anchor to increase ventilation (movement of air).
  • Avoid sunburn.
  • Reduce need for water by avoiding any extra exertion. If you exert yourself, you will sweat and use a lot of fluids.
  • Keep the outside of the raft wet.
  • Wet your clothing during the day with seawater.

Drinking Water

10-107. The normal, healthy body (at rest) can stay alive for over 40 days with no food and as little as 11 ounces (one ration can) of fresh water each day. As little as 2 or 3 ounces of drinking water each day can keep a person healthy for up to 10 days. Without fresh water, a person often becomes delirious in about 4 days and might die in 8 to 12 days.

No Water for First 24 Hours

10-108. Do not issue water during the first 24 hours unless you have an unlimited supply. The body is already full of water. If you drink more, it will probably be wasted in the form of urine. After 24 hours, your body will be drier and will absorb the water you drink, just like a dry sponge will hold water, but a wet sponge will not. If a survivor is injured, you may give him water during the first 24 hours. The survivor will need it to replace the fluid he lost through his bleeding or burns. Only give water if he is conscious.

10-109. After 24 hours, you may issue a full ration (1/3 of a 1-quart can) of water for each person. The ration should be divided into three equal parts. Drink one part at sunrise, one at midday, and one at sunset.

Rainwater

10-110. You may collect more water by catching rainwater. Some parts of the inflatable life raft canopy are designed to catch water. Rainwater catchment tubes will take the water into storage bags on the inside of the raft. The storage bags are in the raft's equipment container. Salt spray may dry on the canopy. The salt might be washed in with the first few ounces of rainwater. It might be very difficult to collect uncontaminated rainwater when the seas are rough and waves are constantly being blown onto the canopy.

10-111. The lookout should alert everyone when it rains. Use and fill all available containers with rainwater (such as equipment accessories bag, ration packs, and empty tin cans). After all of the containers have been filled, everyone should drink as much of the rainwater as they can.

Condensation

10-112. Water might condense on the inside canopy of the inflatable life raft. Use one of the cellulose sponges that is provided in the raft equipment to soak up the water. Squeeze the water out of the sponge to drink or store. Be sure to keep a sponge clean for this purpose.

Snow and Ice

10-113. In the Arctic Sea, you can collect "old saltwater ice." It is bluish in color with smooth, rounded corners. It is usually pure enough to eat or drink. Do not make the mistake of eating "salt ice." "Salt ice" is gray and milky. It should not be eaten.

10-114. Remember, ice and snow will tend to chill your stomach and reduce your body temperature. If you are on the verge of hypothermia, you should not eat ice or snow. Allow it to melt and get as warm as possible. Warm it in your mouth before swallowing.

Never Drink Seawater or Urine

10-115. Rain, ice, and condensation are good sources of water. Do not mix saltwater, urine, or animal fluid with fresh water to stretch your water supply. Drinking seawater will only worsen your thirst and increase water loss by drawing body fluids from the kidneys and intestines. The salt will go to the brain and cause delirium and convulsions. Drinking seawater and urine during a survival situation could cause madness and death.

Obtaining Food

10-116. Do not eat during the first 24 hours. After 24 hours, you may eat 4 ounces each day. In a life raft the food will last 5 days. You will have extra rations (food and water) if the boat or raft is not carrying its full number of passengers.

10-117. Do not eat food if you do not have water. Your body needs water for digesting food. Eating without drinking fresh water could cause death.

Getting Food From the Sea

10-118. The sea has many different forms of life. If you have enough fresh water, you will probably not starve to death. Remember that water is a MUST! Because fish and birds are rich in salt and protein, more water is needed to digest them. Do not eat food from the sea unless you have two or three times more water than your daily ration. DO NOT panic if you do not have enough water to drink with your seafood or if you cannot catch any seafood right away.

10-119. You probably abandoned ship with excess body fat. Your system will begin to use the fat if you do not eat. One pound of body fat will probably keep your system working at about the same rate as two meals. The rate at which body fat and protein are changed to heat and energy depends upon air temperature, your activity, and your mental state. You can live longer on your stored energy if you keep your mind and body relaxed. It also helps if you do not overwork yourself or expose your body to very hot or cold temperatures.

Fish

10-120. Most fish that are found in the open sea can be eaten. If they are found closer to shore they might be poisonous. The puffer, porcupine, and parrot fish are poisonous. They are fish that blow themselves out or have spines or bristles.

10-121. The flesh of fish caught in the open sea is good to eat whether cooked or raw. The heart, liver, and blood of fish are good to eat. Intestinal walls are edible, but the contents may be dangerous unless they are cooked. The stomachs of large fish may contain small fish partly digested, which are good to eat. Fish eyes also contain a lot of water.

10-122. You can catch fish by using the fishing kit provided with your equipment. Complete instructions are inside the kit. If you have lost your fishing kit, you could use the following methods to catch fish:
  • By tying your knife to a paddle, oar, or boat hook, you may be able to spear large fish near the surface. Slash with your knife in schools of small fish.
  • Fishhooks can be made from wood split from the lifeboat. This wood is notched and held together with thread from the equipment or unraveled from cloth (Figure 10-37).
  • A jackknife can be made into a large fishhook. Wedge the blade open with a piece of wood and tie as shown in Figure 10-38.
10-123. Flying fish are probably the most available food. Many survivors have lived on them alone. Some may glide into or against your craft. At night, flying fish (and most other fish) are attracted by light. Shine your light on the side of your white craft or cloth and the flying fish will often glide toward the light and into the boat. Often, a bright moon shining on a white object will draw them.

10-124. If and when you catch more fish than you can eat, in order to drink, squeeze or chew out the juice of the flesh. Fish juice tastes much like the juice of raw oysters or clams. To squeeze it out, cut a piece of fish without bones or skin. Cut it into fine (tiny) pieces. Wrap it in a cloth with long ends. Have two people twist the ends as tight as possible. The juice will drip out. To chew it out, chew a small piece of fish in your mouth. Suck out the juice and swallow it. Spit out the remaining flesh.

10-125. Cut fish into thin, narrow strips and hang them out in the sun to dry. If it completely dried and kept dry, it will often stay good for several days. It may even taste better dried.

IMPORTANT!
Fish that are not cleaned may spoil in half a day.
Clean and immediately eat or dry your fish.


Figure 10-37. Fishhooks Made From Wood


Figure 10-38. Fishhook Made From a Jackknife

Turtles

10-126. All of the meat, blood, and juice of a turtle are good. The best meat is found against the shell, under the backbone. Cut through the ribs to get to this meat. A hot sun brings a clear oil out of turtle fat in which you can dip your food.

CAUTION: A turtle can still bite and scratch even after you have cut off its head.

Seaweed

10-127. Raw seaweeds are tough and salty. They are difficult to digest. Eat them only if you have plenty of fresh water.

10-128. Small edible crabs, shrimp, and fish often live in the seaweed. Lift them out of the water slowly and carefully. Shake them over the survival craft. Get rid of the jellyfish and eat the remaining morsels.

Birds

10-129. All sea birds are nourishing and can be eaten. The blood and liver are also good to drink and eat. Try to catch birds that will sometimes land on you or on or in the survival craft.

10-130. Catch birds by dragging a baited fishhook behind the craft. Pull on the line after they have swallowed the hook. The hook catches the bird like a fish. Catch every bird you can. Use the feathers as fishing lures and the meat and guts for fish bait. Birds can also locate fish for you. When feeding, they usually follow schools of fish. This will give you an opportunity to get right up to the birds to catch them. Also, do not forget to catch the fish they are feeding on.

SEARCH AIR RESCUE

10-131. Upon receiving a signal from any source that a ship or aircraft is in distress, it is the responsibility of all vessels in the area to go to the site and give help to the ship, aircraft, or persons in distress. This signal can range from a ship that is sinking or on fire, a downed aircraft, man overboard, or serious illness or injury aboard ship.

TYPES OF DISTRESS SIGNALS

10-132. A ship at sea can be alerted to an emergency by the following:
  • Radio or radiotelephone.
  • Visual international distress signals.
  • Aircraft.

HOW AIRCRAFT DIRECT SHIPS TO DISTRESS SCENE

10-133. These procedures are used by an aircraft to direct a ship toward another ship or aircraft in distress:
  • The airplane circles over the ship at least once. Then the aircraft crosses the bow of the ship as close as possible. At a low altitude, the pilot opens and closes the throttle or changes the propeller pitch (Figure 10-39).
  • Then the airplane will head in the direction that the ship is to follow in order to find the ship or aircraft in distress (Figure 10-40).
  • If help is no longer required, the aircraft will return and fly, opening and closing the throttle or changing the propeller pitch, across the wake of the ship at a low altitude and as close astern as possible.


Figure 10-39. Aircraft Signal


Figure 10-40. Aircraft Dismissal Signal

SURFACE SHIPS ACTION

10-134. Once your ship has been alerted to the distress situation, you will acknowledge the receipt of the message. You will also provide a continuous radio guard on 2182 kHz and/or channel 16 on the radiotelephone, and, if required, retransmit the distress message to the ships in the area.

10-135. The next step is to determine your exact position and the position of the vessel or aircraft in distress. If it is possible, you should communicate the following to the ship in distress:
  • Your identity.
  • Your position.
  • Your speed and ETA.
  • Your true bearing from the vessel.
Then the entire crew of your ship is to start preparing for the rescue as follows:
  • Get heaving lines, ladders, and scramble nets rigged on both sides of the vessel.
  • Prepare to receive survivors who may need medical assistance.
  • Put lines over ship's side to assist any lifeboats or rafts that may secure alongside.

ASSISTING AN AIRCRAFT THAT MAY DITCH

10-136. Make a smoke signal if possible to show the pilot direction of surface wind. At night, show deck lights and shine the signal lamp straight up in the air. Do not shine it on the aircraft. You may blind the pilot. Try to make radiotelephone contact with the aircraft and give the following information:
  • Wind direction and force.
  • Direction, height, and length between the swells.
  • Any other information the pilot may require.
Proceed alongside the aircraft as quickly as possible. The aircraft may break up as soon as it hits the water.

Note: Military aircraft are usually fitted with "ejection seats." Many times the crew will use their ejection seats rather than ditch with the aircraft.

10-137. When picking up survivors from a military aircraft, get the following information as soon as possible and, if necessary, pass the information to other rescue ships by radiotelephone:
  • What was the time and date of the casualty?
  • Did you bail out or was the aircraft ditched?
  • If you bailed out, at what altitude?
  • How many others did you see leave the aircraft by parachute?
  • How many ditched with the aircraft?
  • How many did you see leave the aircraft after ditching?
  • How many survivors did you see in the water?
  • What flotation gear did they have?
  • What was the total number of persons aboard the aircraft before the accident?

PREPARATION FOR MEDICAL EVACUATION OF PERSONNEL FROM YOUR SHIP

10-138. If there is a serious injury aboard your ship, a helicopter may be used to remove the injured crew members. This may be a Coast Guard, Army, Navy, or Marine helicopter performing the rescue mission. The ship's master and crew should prepare for removing the crew member while waiting for the rescue helicopter. The following is a complete helicopter evacuation checkoff list. When requesting helicopter assistance:
  • Give accurate position, time, speed, course, weather conditions, wind direction and velocity, voice and CW frequencies.
  • If not already provided, give complete medical information, including whether or not the patient can walk.
  • If you are beyond helicopter range, advise your diversion intentions so that a rendezvous point may be arranged.
  • If there are any changes, advise immediately. Should the patient die prior to arrival of the helicopter, be sure to advise.
Remember that members of the flight crew are risking their lives attempting to help you. Make the following preparations prior to arrival of the helicopter:
  • Provide continuous radio guard on 2182 kHz or specified VOICE frequency, if possible. The helicopter cannot operate CW.
  • Select and clear the hoist area, preferably aft, with a minimum 50-foot radius. This must include securing loose gear, awnings, and antenna wires. Trice up running rigging and booms. If the hoist if aft, lower flagstaff.
  • If hoist is at night, light up pickup area as well as possible. BE SURE YOU DO NOT SHINE ANY LIGHTS ON THE HELICOPTER. If there are obstructions in the vicinity, put a light on them so the pilot will be aware of their positions.
  • Point searchlights vertically to aid in locating the ship, and secure them when helicopter is on scene.
  • Advise location of pickup area BEFORE the helicopter arrives, so that the pilot may make his approach aft, amidships, or forward, as required.
  • Arrange a set of hand signals among the crew who will assist. There will be a high noise level under the helicopter, making voice communication almost impossible.

HOIST OPERATIONS

10-139. Hoisting operations are used to rescue or evacuate personnel from a number of dangerous situations. The following are some guidelines to follow when using hoisting operations:
  • If possible, move the patient to a position as close to the hoist area as his condition permits--TIME IS IMPORTANT.
  • It may be necessary to move the patient by litter. Be prepared to do this as quickly as possible. Be sure patient is strapped in, face up, with life jacket, if his condition permits.
  • Be sure patient is tagged to indicate what medication, if any, was administered, and when.
  • Have patient's medical record and necessary papers in envelope or package ready for transfer WITH him.
  • Change course so the ship rides as easily as possible with the wind on the bow, preferably on the port bow. Once established, maintain course and speed.
  • Reduce speed, if necessary, to ease ship's motion; but maintain steerageway.
  • If you do not have radio contact with rescue aircraft, when you are in all respects ready for the hoist, signal the aircraft with a "come on" by hand, or at night by flashlight.
  • To avoid static shock, let basket or stretcher touch the deck before handling.
  • If the aircraft drops the trail line, guide the basket or stretcher to deck with line. Keep line clear at all times.
  • Place patient in basket, sitting with hands clear of sides, or in the litter as described above. Signal hoist operator when ready for hoist. Patient signals by nodding head if he is able. Deck personnel give thumbs up.
  • If necessary to take litter away from hoist point, unhook hoist cable and keep free for aircraft to haul in. DO NOT SECURE CABLE TO VESSEL OR ATTEMPT TO MOVE STRETCHER WITHOUT UNHOOKING.
  • When patient is strapped in stretcher, signal aircraft to lower cable, hook up, and signal hoist operator when ready to hoist. Steady stretcher from turning or swinging.
  • If trail line is attached to basket or stretcher, use to steady. Keep feet clear of line.

HELICOPTER HOIST PROCEDURES

10-140. The wind developed by the helicopter rotor system can be over 70 knots. It is important to have all loose gear, on deck, securely tied down or stowed below decks. The rotor system could be destroyed if any loose objects are blown into the rotor during the hoist.

10-141. It is important to plan ahead because your voice cannot be heard over the noise made by the helicopter engine. Work out problems that may occur before the helicopter hovers overhead. Do not forget to wear your life jacket! 10-142. A helicopter might be used to rescue survivors or evacuate injured mariners by rescue basket, rescue sling, and stokes litter (Figure 10-41).


Figure 10-41. Rescue Basket Hoist

Rescue Basket

10-143. The US Coast Guard usually uses a rescue basket for survivors who can help themselves (Figure 10-42). The basket is very easy to use. Just climb into the basket after it touches the deck (to discharge static electricity), sit down, and keep hands and arms inside.


Figure 10-42. Rescue Basket

Rescue Sling

10-144. A rescue sling is carried on board helicopters. Rescue helicopters from other countries, use the sling more often than by the US Coast Guard. The rescue sling is just a padded loop that is placed over the body and underneath the armpits. The arms are held around the sling as shown in Figure 10-43.


Figure 10-43. Rescue Sling

 

Stokes Litter
10-145. This type of litter will usually be used to hoist those who have serious injuries or illnesses or who are unable to walk. To use the litter, it is necessary to get help from other crew members. The straps must be disconnected and spread out. The blankets must be removed. The patient should be put in the litter and covered with the blanket. The straps are then snugly fastened with the pad on top of the chest as shown in Figure 10-44.


Figure 10-44. Stokes Litter

10-146. If the litter has to be taken below decks to the patient, it must be unhooked from the cable. This hook must not be attached to any part of the vessel. There is always a possibility that there may be an emergency aboard the helicopter itself. The helicopter may have to move unexpectedly. To decrease this type of danger, the pilot may hover off to one side of the vessel while waiting.

10-147. If a steadying line is attached to the basket, horse collar, or litter, it must be tended. This will stop the rescue device from swinging too much. It is very important that the rescue device touches the vessel before anyone touches it. As soon as the object being lowered touches the deck, static electricity (which builds up in the helicopter during flight) will be discharged. Never shine lights on the helicopter. It will blind the pilot.

Ready to Hoist

10-148. To signal the helicopter pilot that all is ready for hoisting, give him a thumbs-up signal, or if you are a patient, nod your head if you are able.

SHIPBOARD NBC DEFENSE

10-149. Much of your military training is dedicated to NBC training in a land combat situation and the protective measures to be taken for survival. This paragraph will discuss NBC countermeasures to be taken aboard ship for survival. Although a nuclear detonation is devastating, survival is possible, and aboard ship it is probable. Your survival will depend upon the actions taken before, during, and after the attack.
TYPES OF NUCLEAR BURSTS
10-150. The energy yield of a nuclear weapon is described in terms of the amount of TNT that would be required to release a similar amount of energy. A nuclear weapon capable of releasing an amount of energy equivalent to the energy released by 20,000 tons of TNT is said to be a 20-KT weapon. A nuclear weapon capable of releasing an amount of energy equivalent to the energy released by 1,000,000 tons of TNT is said to be a 1-MT weapon.

10-151. Weapon yields may range from a fraction of a KT to many MTs. Although a weapon's total yield is not significantly influenced by the environment about the burst point, the relative importance of weapon effects depends greatly on where the detonation takes place. The four types of bursts are high altitude, air, surface, and underwater.

10-152. Although the four types of bursts are defined below, there is actually no clear line of demarcation between them. Obviously, as the height of burst is decreased, the high altitude burst becomes an air burst, an air burst will become a surface burst, and so forth. The significant military effects associated with each type of burst follow.

High Altitude Burst

10-153. This explosion takes place at an altitude in excess of 100,000 feet. It produces airblast, thermal radiation, an EMP, initial nuclear radiation, and atmospheric ionization. At altitudes above 100,000 feet, the proportion of energy appearing as blast decreases markedly, while the proportion of radiation energy increases. Due to the low density of the atmosphere, the range of the initial nuclear radiation increases. In contrast to explosions below 50,000 feet, the attendant atmospheric ionization from bursts above 100,000 feet lasts for minutes to hours. The important consequences of high altitude bursts are the damage to weapons systems or satellites operating in the upper atmosphere or in space, and the effects on electromagnetic waves (communications and radar) relying on propagation through or near the region of the burst.

Air Burst

10-154. In this type of burst, the fireball does not contact the surface. An air burst produces airblast, thermal radiation (heat and light), EMP, and initial nuclear radiation (neutron and gamma rays) about the burst point. There will be no significant residual nuclear radiation (gamma and beta radiations from airborne or deposited radioactive material) except when rain or snow falls through the radioactive cloud.

Surface Burst

10-155. The fireball touches or intersects the surface. A surface burst produces airblast, thermal radiation, EMP, initial nuclear radiation around surface zero, and residual (transit and deposit) nuclear radiations around SZ and downwind from SZ. Transit radiation is produced by airborne radioactive material (base surge/fallout) and deposit radiation is produced by radioactive material (base surge/fallout) collection on exposed surfaces. Surface bursts over water will also produce underwater shock and surface water waves, but these effects will be of less importance. Over land, earth shock will be produced, but will not be an important effect at any significant distance from the burst point.

Underwater Burst

10-156. This burst occurs below the water surface. It produces underwater shock and a water plume, which then causes a base surge. Very shallow bursts may also produce airblast, initial nuclear radiation, fallout, and possibly some thermal radiation. These effects will be reduced in magnitude from those of a water surface burst and will become rapidly insignificant as the depth of burst is increased. The damage range due to shock is increased as depth of burst is increased. For a given weapon yield, greater hull and machinery damage will be produced by shock from an underwater burst than by airblast from an air or surface burst.

10-157. When a high yield weapon is detonated underwater in the deep waters adjacent to a continental shelf, large breaking waves may be generated by the upsurge along the shelf slope. These waves will appear on the shallow water side of the shelf edge. They are characterized by a long period with a sharp, possibly breaking, crest. They dissipate in amplitude as they progress toward the shore. Calculations and simulation experiments with the East Coast US continental shelf indicate that, in the near vicinity of the shelf edge (shallow water side only), these waves may be large enough to damage the largest combatant ships and swamp or capsize smaller ships. This shoaling phenomenon does not appear in deep water. Except in shoaling waters, water waves normally will not be a major hazard.

UNDERWATER SHOCK

10-158. Underwater shock is the shock wave produced in water by an explosion. The shock wave initially travels several times the speed of sound in water, but quickly slows down to sonic speed (about 5,000 feet per second). Underwater shock produces rapid accelerations that may result in equipment and machinery disarrangements, hull rupture, and/or personnel injuries. Both the directly transmitted shock wave and the shock wave reflected from the sea bottom can be damaging. An underwater explosion produces a shock wave similar to an air burst. Four factors determine whether the greater damage will be caused by the direct wave or the reflected wave:
  • Distance from burst.
  • Depth of burst.
  • Depth of water.
  • Bottom configuration and structure.

THERMAL RADIATION

10-159. Thermal radiation is the radiant energy (heat and light) emitted by the fireball. Thermal radiation travels at the speed of light and persists as long as the fireball is luminous. The duration of thermal radiation emission depends on weapon yield. It usually lasts less than 1 second for 1-KT yield and about 8 or 9 seconds for a 1-MT yield. Thermal radiation is effectively shielded by anything that will cast a shadow (opaque materials). Thermal radiation can produce combat ineffectiveness (that is, individuals unable to man battle stations) among exposed personnel by skin burns, flash blindness, or retinal burns.

10-160. Thermal radiation is modified by the height of burst, weapon yield, cloud cover, and terrain features. As height of burst is increased, the area of the earth's surface exposed to thermal radiation increases. This happens because there are fewer shadows from existing structures (such as vegetation, terrain features, and so forth).

10-161. As weapon yield increases, the range at which thermal radiation can cause skin burns and eye injuries to exposed individuals extends well beyond the range where blast and initial nuclear radiation are of significance. The rate at which thermal radiation is emitted from a high-yield weapon is slower than for a low-yield weapon. Therefore, the high-yield weapon must deliver more thermal energy to do an equivalent degree of damage because a target has more time to dissipate the heat being received.

NUCLEAR RADIATION

10-162. The four basic types of nuclear radiation given off during a nuclear explosion are alpha particles, beta particles, gamma rays, and neutrons.
  • Alpha particles. These do not travel more than a few centimeters in air without being stopped. They cannot penetrate even a thin sheet of paper.
  • Beta particles. These may travel several feet in the air, but they cannot penetrate a sheet of aluminum more than a few millimeters in thickness. Beta particles cannot penetrate the normal combat uniform.
  • Gamma rays. These are a form of electromagnetic radiation, indistinguishable from X-rays.
  • Neutrons. These are electrically neutral particles. Gamma rays and neutrons can travel comparable distances in the air, up to several hundred meters. Gamma rays and neutrons have the greatest penetrating power of all the forms of nuclear radiation, and their injurious effects on personnel are quite similar.
10-163. Nuclear radiation does not affect most materials in any visible manner. Therefore, the essential value of ships, vehicles, electronic equipment (except transistors), and other equipment is not impaired by radiation. However, radioactive contamination does pose a danger to operating personnel. The term CONTAMINATION is used to mean radioactive material that has been deposited in a location where it is not desired. All radioactive contamination gives off nuclear radiations.

INITIAL NUCLEAR RADIATION

10-164. Initial nuclear radiation is defined as the radiation (essentially neutrons and gamma rays) emitted by the fireball and the cloud during the first minute after detonation. Depending on weapon yield, all significant neutron radiation is emitted in less than 0.1 second, gamma radiation up to 20 or 30 seconds. The 1-minute time limit is set as the maximum time for the nuclear cloud to rise beyond the range in the air at which gamma radiation is a significant hazard. Initial nuclear radiation generally may not produce significant material damage, but will produce combat ineffectiveness.

NUCLEAR RADIATION INJURY

10-165. The radiological hazards described are those which might be of significance to the military effectiveness of marine personnel in combat operations. Injuries to personnel can result from exposure to sufficient quantities of either initial or residual radiation, or a combination of the two. Unlike injuries from other weapon effects, nuclear ionizing radiation injuries may not become evident immediately unless a high dose is received. All nuclear radiation, even in very small doses, has some harmful effect on the body and should be avoided whenever possible.

10-166. The biological injury to an individual from nuclear radiation depends on many factors. Some of these factors include the following:
  • Radiation dose received.
  • Partial or whole-body exposure (all radiation doses referred to are due to external whole-body exposures to penetrating radiation).
  • Period over which the dose is received.
  • Variations in the body's resistance to radiation injury including those due to physical condition, sex, and age.
  • Previous radiation exposure.
  • Presence or absence of other injuries.
  • Periods of recuperation between periods of radiological exposure.

FALLOUT

10-167. Fallout, a major effect of a shallow underground and underwater burst, is the radioactive material that falls from the nuclear cloud and deposits on exposed surfaces. The fallout primarily consists of fission products (gamma and beta emitters) mixed with material vaporized by the fireball and drawn up into the nuclear cloud. Fallout, whether airborne or deposited, is a hazard because it emits gamma radiation that can penetrate ship structures, buildings, and aircraft. It can also cause radiation injury or death to personnel. Deposited fallout also presents a personnel contamination hazard.

10-168. The area of fallout is determined by the wind structure up to the top of the cloud. In complete calm, the fallout pattern is roughly circular. A constant wind direction leads to an elongation of the pattern. Complicated wind patterns (wind shear) as well as variations in wind pattern in time and space lead to complicated ground patterns. Fallout is difficult to predict accurately except under calm and very stable wind conditions.

10-169. Reduction in yield or changing the height/depth of burst to a point where the fireball does not intersect the ground will reduce fallout, as will complete containment of an underground burst.

10-170. Fallout landing on water will sink and will not constitute a hazard to ships passing through the area after fallout cessation. Fallout over a land area will remain on the surface and will be a hazard to personnel living in or passing through the area. In time, the fallout on a land surface will decay to an insignificant level.

PROTECTIVE SHIELDING

10-171. Protective shielding is one method of defense against nuclear radiation. The tremendous penetrating power of gamma rays makes it difficult to provide enough shielding to protect personnel from gamma rays. However, the structure of the ship provides some protection against them.

10-172. The main materials likely to provide shielding aboard a ship are steel plating, piping, machinery, water, fuel oil, and some types of wood. Shielding materials at storage facilities include concrete and earth.

10-173. The amount of shielding required to stop gamma rays is measured in half-value layer thickness or "half-thickness," for short. A half-thickness is defined as the amount of material necessary to cut down the amount of radiation to one half of its original value. The half-thickness value for each material is different. For example, a concrete shield about 6 inches thick or an earth shield about 7 1/2 inches thick will cut the gamma radiation in half. Suppose that you are standing at a plate where the gamma radiation is 400 roentgens. If you are behind a half-value layer thickness of some kind at the time, you will receive a dose of 200 roentgens. Now suppose you are standing behind two shields, each of which is a half-value layer. The 400 roentgens of gamma radiation is reduced to 200 roentgens by the first half-thickness and to 100 by the second half-thickness. With each additional half-thickness shield, you reduce the remaining gamma radiation by half. Remember that these thicknesses do not stop gamma radiation altogether; instead, they cut it in half. In a nuclear attack, one-half value layer of steel or concrete might be just enough of a shield to keep you from getting a lethal dose of gamma radiation.

10-174. The approximate half-thickness of some materials, listed in order of their effectiveness as shields against gamma radiation, are shown in Table 10-2.

Table 10-2. Materials Effectiveness Against Gamma Radiation

 

INITIAL

RESIDUAL

     

Steel

1.5 inches

0.7 inches

Concrete

6.0 inches

2.2 inches

Earth

7.5 inches

3.3 inches

Water

13.0 inches

4.8 inches

Wood

23.0 inches

8.8 inches

PREVENTIVE MEASURES (BEFORE ATTACK)

10-175. Personnel should take preventive measures before an attack. The steps that are listed are not in a required sequence, they only list the things that should be performed. The situation at the time will determine the sequence.
  • Notify all ship's masters and coxswains. They must take immediate charge of the situation aboard their vessel.
  • Sound the NBC alarm.
  • Shut all watertight doors, ports, and ventilation systems.
  • Cease all cargo operations.
  • Get away from the pier or beach, and put out to sea.
  • Get all "soft" items off the decks, such as wood, hawsers, line, canvas, and so on.
  • If the vessel is not equipped with a washdown system, rig the fire hoses for washdown.
  • Commence washing the vessel down.
  • Secure all loose gear inside the vessel.
  • Have personnel don their protective clothing.
  • Get personnel to take cover in interior of the vessel. Get them as far down below the centerline and in between the engines as possible.
Note: If the vessel is 1,000 yards or more from "ground zero," the crew should survive. With the crew below the waterline and in between the engines, the bulkheads, engines, ship's hull, and the water all provide a shield against radiation.

Personnel should also take the necessary actions against a nuclear attack. Table 10-3 shows the actions personnel should take during nuclear denotations.

Table 10-3. Recommended Personnel Action Against Nuclear Detonations

 

WITH WARNING

NO WARNING

BURST

TYPE

TOPSIDE

PERSONNEL

BELOW DECK

PERSONNEL

TOPSIDE

PERSONNEL

Air

A

B

C

Surface

A

B

C

Underwater

B

B

 
       

A -LIE PRONE AND HOLD ON TO SOLID SHIP STRUCTURE.

B - STAND WITH KNEES FLEXED AND HOLD ON TO SOLID SHIP STRUCTURE.

C - HANDS-TO-FACE EVASION.

PREVENTIVE MEASURES (DURING AN ATTACK)

10-176. Personnel should take preventive measures during an attack. The following are some precautions to take:
  • DO NOT eat, drink, or smoke.
  • Brace yourself and hold on to a secure object.
  • Continue the washdown system for at least 1 hour.
  • Keep all cuts or open wounds bandaged.
  • At the sign of brightness, shut your eyes and turn your face away.
Note: When you are in an open topside area (where you can quickly drop to the deck) and you see the flash or see the sky light up, close your eyes and immediately raise your hands to cover your face. Meanwhile, drop to the deck as quickly as possible. Use your shoulder, not your hands, to break a fall. Curl up to present a minimum target. You may feel the heat from the detonation. Two to 5 seconds after the flash (depending on the weapon yield) or after the heat sensation is over, remove your hands from your face. Then immediately and firmly, grab a solid ship structure to prevent the airblast winds from blowing you overboard or against the ship's structure. You may suffer flash blindness for a period up to 30 minutes.

PROTECTIVE MEASURES (AFTER THE ATTACK)

10-177. Personnel should take preventive measures after an attack. The following are some precautions to take:
  • Maintain maximum speed. Put the vessel on a course that is crosswind and away from the point of detonation.
  • Continue the washdown for at least 1 hour.
  • Do not eat, drink, or smoke.
  • Check the interior of vessel for watertight integrity.
  • Observe the fallout pattern and continue to leave the ventilation system shut off.
  • If radiac instruments are on board ship, monitor interior of vessel, all open food, liquids, and cigarettes.
  • Don protective clothing before going on deck.
  • Commence vessel washdown.

RADIOLOGICAL DECONTAMINATION

10-178. This neither neutralizes nor destroys the contamination. Instead, it merely removes the contamination from one particular area and transfers it to an area in which it presents less of a hazard. At sea, dispose of radioactive material directly over the side.

10-179. Flushing with water, preferably water under high pressure, is the most practicable way of rapidly decontaminating topside surfaces. Aboard ship, a water washdown system is used to wash down all the exterior surfaces (from high to low and from bow to stern). The washdown system consists of piping and a series of nozzles that are specially designed to throw a large spray pattern on weather decks and other surfaces. Permanent washdown systems are being built into ships under construction or conversion. Interim washdown system kits are provided for ships already in service.

10-180. If the washdown system is turned on before the arrival of contamination, the system prevents heavy contamination of the ship by coating the weather surfaces with the flowing stream of water. The flowing stream of water carries away radioactive particles as they fall on the ship and keeps radioactive particles from settling into cracks and crevices.

10-181. If some areas of the ship become heavily contaminated before the washdown system is activated, it will probably be necessary to hose down such areas vigorously, using seawater under pressure. Hosing should proceed from higher to lower surfaces, from bow to stern, and, if possible, from the windward side to the lee side. Every possible precaution should be taken to see that contaminated water does not flow back over cleaned areas. Precautions must also be taken to see that contaminated water is not hosed into the interior of the ship through vents, doors, or hatches. The hose should be directed so that the water strikes the surface about 8 feet from the nozzle. The hose stream should sweep horizontally from side to side, moving lower on each sweep. The hosed areas should be overlapped somewhat on each sweep to ensure complete washing. The runoff should be directed into scuppers and deck drains as rapidly as possible to keep the contaminated water moving and to prevent pools of contaminated water from forming.

10-182. Hosing down will be most effective if it is done before metal or painted surfaces have dried after contaminating material has been deposited. However, contamination that has been deposited despite washdown will also resist hosing alone. Vigorous scrubbing with deck brushes and detergents, followed by hosing, is required. Ships without washdown systems will initially decontaminate by hosing down with seawater as soon as the tactical situation permits.

CONTAMINATION MARKERS

10-183. Areas or objects that are contaminated by NBC attack must be clearly marked to warn personnel approaching the area of the existence of hazards. Contamination markers should outline dangerous areas and establish boundaries within which safety control must be exercised. Radiation hot spots--that is, areas having radiation intensities significantly greater than the general radiation level of the surrounding areas -- should be identified.

10-184. The standard NATO system for marking areas, that are contaminated by NBC attack, is used. Figure 10-45, shows these standard survey markers. Each marker is in the shape of a right triangle; one side of the triangle is about 11 1/2 inches long, and the other two sides are about 8 inches long. The markers may be made of wood, metal, plastic, or other rigid material.


Figure 10-45. NATO NBC Markers

 



NEWSLETTER
Join the GlobalSecurity.org mailing list



US Policy Toward Africa: Eight Decades of Realpolitik - Herman J Cohen's Latest Book