cover or envelope. The preserver has cloth tapes to pull tight for a close fit. Leg straps prevent it from riding up while you are in the water. A body strap across the chest helps give a snug fit and provides a hold for lifting you out of the water. You can also use the strap to attach yourself to a life raft or to other persons in the water. Put on the vest type of life preserver over your clothing. Tie the upper tapes to make it fit comfortably, and pull the tape at the waist fairly tight to keep the preserver from sliding up in the water. Then adjust the chest strap and fasten the snap hook into the ring. Pull the leg straps as tight as possible without producing discomfort. Tie the collar tapes tightly under the chin. The collar holds the head upright and helps prevent an unconscious person from drowning. INFLATABLE  TYPE.—The  inflatable  life preserver  (fig.  15-5)  is  made  of  lightweight, neoprene-coated nylon. It’s carried in a pouch container held around your waist on a web belt. You blow up the inflatable  preserver  either  by  mouth  or  by  using  a carbon dioxide (CO₂ ) cylinder. It’s equipped with a lifting harness, a waist belt, and a wooden toggle and a line  for  attaching  yourself  to  a  life  raft  or  another survivor.  Take  the  following  steps  when  using  the inflatable life preserver: 1.  Pull the pouch around to the front, remove the preserver from its pouch, and slip it over your head. 2.  Grasp the lanyard attached to the CO 2 cylinder and jerk downward.   If you need more buoy- ancy, the life preserver can be orally inflated by taking the following steps: a.  Turn down the knurled ring at the base of the oral inflation tube as far as it will go. b.  Depress  the  mouthpiece  by  force  of  the mouth, and blow into the tube as if you were blowing up a balloon. c.  Release the mouthpiece when inhaling to prevent escape of the air. 3.  When the preserver is inflated, lock the oral valve by turning the knurled ring against the mouthpiece. NOTE Always wait until you have entered the water to inflate this type of life preserver. The  automatically  inflatable  work-type  life p r e s e r ve r  p r ov i d e s  y o u  m a x i m u m  l i f e s av i n g protection. At the same time, it doesn’t interfere with the  jobs  you  do,  such  as  working  over  the  side, performing underway replenishment (UNREP) duties, working as part of a boat crew, or manning selected battle stations. The automatically inflatable work-type life preserver will— Inflate the life preserver if you go into the water in an unconscious or helpless state. Allow you to inflate the auto inflatable preserver orally by the auto function device or by using a combination of the two. T h e  a u t o - f u n c t i o n  d ev i c e  u s e s  a  w a t e r - degradable paper to release a spring that causes two CO₂    cylinders  to  be  punctured  and  inflate  the preserver. PIN-ON LIGHTS.—Small watertight flashlights or chemically activated light sticks have been developed for use with life preservers to help rescuers see a person in the water more easily at night. The flashlight consists of  a  one-cell  battery  case  to  which  is  permanently attached a heavy metal safety pin for fastening the light to the preserver. The lens is dome-shaped, providing 360E visibility from above. The chemically activated light sticks are activated by a chemical reaction in the stick. Wear  these  lights  whenever  you  use  the  life preserver. Check the battery at least once a week to see that it works. Replace the battery at least every 6 months. Check the light stick each time you use the preserver, and replace it if you see any indication that the stick has been damaged or used. Remember the following tips when using these lights: On the vest-type preserver, pin the light near the top  of  your  shoulder  so  that  the  lens  points upward. When  pinning  the  light  on  the  vest-type preserver, take care not to pierce the waterproof 15-6 Student Notes: