The early symptoms of heatstroke are similar to those   of   heat   exhaustion–headache,   nausea,   and dizziness. At first, the victim’s breathing is deep and rapid;   but,   as   the   symptoms   progress,   breathing becomes  shallow,  almost  absent.  The  skin  appears flushed, dry, and very hot. The pupils are constricted to a pinpoint; the pulse is fast and strong. It is extremely important that you recognize the differences between heat  exhaustion  and  heatstroke.  HEATSTROKE  IS  A TRUE LIFE-AND-DEATH EMERGENCY. The  most  important  first-aid  treatment  for  a heatstroke victim is to lower the victim’s body heat. Move the victim to a cool place. Douse the victim with cold water. Remove as much of the victim’s clothing as possible  to  allow  free  flow  of  air  over  the  body  to promote cooling. If the victim is conscious, give him/her cool water to drink. Transport the victim to a medical facility as quickly as possible. So far, we have discussed heat-related problems and the first-aid treatment for heat stress. However, you will be  much  better  off  if  you  learn  what  you  can  do  to prevent heat stress. PREVENTION In spaces where heat stress is likely to occur, it is difficult  to  lower  temperatures.  Therefore,  preventing heat stress-related conditions is the goal. Monitoring conditions that bring about heat stress and controlling the crew’s exposure to high-heat and high-humidity conditions reduces the chances of heat stress. Some of the factors that cause heat stress are as follows: l  Unnecessary  heat  and  humidity  sources l Steam leaks . Damaged insulation Report  these  types  of  conditions  so  they  can  be corrected. Vents and exhaust blowers should be adjusted to maintain proper air circulation. On  board  ship,  spaces  are  ventilated  by  ductwork connected to supply (intake) and exhaust blowers. These blowers  (or  fans)  are  driven  by  two-speed  electric motors. Exhaust fans have a greater air-moving capacity than  supply  fans.  Unless  personnel  are  otherwise directed, supply and exhaust ventilation fans are set to the SAME speed. It is important that you understand the need  to  MAINTAIN  FLOW.  If  you  do  not  MAINTAIN FLOW, the following could happen to you. A watch stander in a hot space sets the supply blower to high speed and then stands under the outlet. Usually, you can tell whether the speed of the vent blowers for a space is set correctly by how hard it is for you to open or shut the doors to the space. For example, if a door opens outward and it is hard to close, then the space  has  a  POSITIVE  pressure.  This  means  that  the supply  vent  is  probably  set  on  high  speed,  and  the exhaust vent is set on low speed. Another   common   problem   with   shipboard ventilation  systems  is  improper  care  of  system  filters. Filters are installed at the intake of the supply blowers to prevent dust and dirt from entering the ship. Cleaning these falters is considered to be routine maintenance. If, however,  filter  cleaning  is  neglected  or  is  poorly  done, the  temperature  of  shipboard  working  and  living  spaces increases because there is a reduced flow of coding air. Spaces considered to be heat-stress areas should contain a  heat-stress  monitor  to  measure  the  heat-stress conditions. On an individual level, wear clothing so there is some air circulation between the clothing and your body. Whenever you perform heavy physical labor, eat lightly and take a rest period before resuming heavy exertion. The   Navy   has   established   strict   space environmental monitoring requirements for heat-stress conditions. These  heat-stress  surveys,  together  with strict exposure limit standard tables, control the amount of time a person may remain in certain high-temperature and high-humidity conditions before being REQUIRED to go to a cool place and rest. For more information about heat injury, you should refer to  Shipboard  Heat Stress Control and Personnel Protection,  OPNAVINST 5100.20 (series), and  Navy Occupational Safety and Health  (NAVOSH)  program  Manual  for  Forces  Afloat, OPNAVINST  5100.19  (series). Heat illnesses and injuries are primarily caused by the  loss  of  body  fluids  and  salts.  Preventing  these illnesses  and  injuries  centers  on  replacing  body  fluids and salts, monitoring the environment, and controlling exposure. For example, in a hot environment, fluids must be replaced ounce for ounce. Therefore, when you are  sweating  heavily,  increase  your  water  intake proportionately. Meals provide salts to replace those lost through sweating. Therefore, if you work in a high-heat and   high-humidity   environment,   you   should   eat well-balanced meals at regular intervals, salted to taste. You should get at least 6 hours of sleep every 24 hours. Wear clean clothing made from at least 35 percent cotton. Do NOT wear starched clothing. Do NOT 13-2