FORT SAM HOUSTON, Texas –
Many people succumb to heat-related illnesses and even death
due to inexperience with extreme summer temperatures and humidity or a lack of
caution outdoors. Military personnel in the San Antonio area are especially
vulnerable to heat-related injuries because of exposure during training or duty
requirements.
“Since the start of the fiscal year we have had 5,694
heat-related injuries across Joint Base San Antonio,” said Staff Sgt. Jerome
Montoya, noncommissioned officer in charge of the Environmental Health Section
at Brooke Army Medical Center on JBSA-Fort Sam Houston.
A majority of the reported injuries were due to dehydration
or a lack of electrolytes, Montoya said; but a plethora of other types of heat
injuries such as sunburn and photokeratitis – a painful sunburn of the cornea
of the eyes – were also reported that could have easily been avoided.
Montoya advised that although no heat-related deaths have
been reported and the majority of injuries were a result of improper hydration
or drinking alcohol, once a person has had a heat-related injury, he or she may
be more susceptible to another heat injury that could lead to death.
“Once you have become a heat casualty you are deemed high
risk, because not all casualties recover completely from the initial injury,”
Montoya explained.
The sergeant pointed out that first heat injury may result
in the body’s susceptibility to a follow-on injury especially during a repeat
of the previous situation, such as inadequate hydration during training.
Adequate hydration translates to consuming both the proper
amounts and types of fluids. So what is the proper intake of fluids?
In an online article (http://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/water/art-20044256),
Mayo Clinic staff say studies have produced varying recommendations over the
years, but that an individual’s water needs depend on many factors including
health, activity level and location.
The Institute of Medicine determined that adequate intake
for an average, healthy male is roughly about 13 cups or 3 liters of fluids a
day. Adequate intake for an average, healthy female is about nine cups or 2.2
liters of total fluids per day.
Total fluids includes water, sports drinks, juice, milk and
soup but not sugary, caffeinated or alcoholic beverages.
“People who are more active should drink more water to
sustain the amount of water they lose while sweating,” Montoya recommends. “The
best way to remember the amount is the ‘8-by-8 rule’ which is drink 8
eight-ounce glasses a day, which equates to 1.9 liters.”
Drinking too much water may also be hazardous to one’s
health.
Hypernatremia, also known as water intoxication, is caused
by the failure to maintain correct levels of sodium in the body that is lost
through sweating.
The signs are similar to dehydration such as nausea,
disorientation, muscle cramps and mainly occurs during competition in events
lasting for several hours, Montoya explained. He said drinking sports drinks or
a simple glass of salt water prevents this injury from occurring.
Alcohol should be avoided during hot weather because it
alters mental status. Generally, an individual consumes alcohol to quench
thirst, which lowers water intake and actually creates dehydration.
Playing sports during summer barbeques while drinking is a
common scenario where heat injuries from lack of hydration occur Montoya said.
He added that although caffeine and sugary drinks served at parties don’t alter
mental status, they are diuretics which increase urine production ultimately
reducing the amount of water in the body and should be avoided as much as
possible.
Training or duty risks for military personnel outdoors are
mitigated via the Wet Bulb Globe Temperature Index, a tool used to prevent heat
injuries. According to the WBGT Index, 5 degrees Fahrenheit should be added to
the environmental temperature if a member is wearing a rucksack or body armor
and 10 degrees Fahrenheit if in Mission Oriented Protective Posture, or MOPP, 4
gear.
The WBGT Index is a heat stress indicator used to gauge the
relative severity of environmental temperature on the human body by measuring
humidity, wind speed or wind chill and visible and infrared radiation, or
sunlight, and then compositing the information into an actual temperature
experienced by personnel.
Derived from a combination of temperatures from three
thermometers – wet globe for humidity, black globe for solar factor, and dry
bulb for ambient levels – the WBGT is a unit set on a tripod in full sunlight.
The index consists of five color-coded categories with
associated temperature information derived from the WBGT and specifies fluid
intake requirements and work allowed. Flags with corresponding colors are flown
to indicate current heat-work conditions.
Black is at the bottom of the index and signals hazardous
working conditions.
“Most training may be restricted during black flag
conditions, based on commander directives,” said Ken Talley, an industrial
hygienist with the 559th Aerospace Medical Squadron/Bio-Environmental
Engineering.
Talley explained that a WBGT is located at Joint Base San
Antonio-Lackland Bioenvironmental Engineering and the Lackland Basic
Expeditionary Airman Skills Training, or BEAST – the Airmen recruit training
site on Joint Base San Antonio-Lackland.
“We record temperatures on an hourly basis and transmit the
information via a call to the command post,” Talley said. “The command post
sends an email notifying units of the flag condition."
A WBGT is located at the 359th JBSA-Randolph clinic
building, explained Airman 1st Class Tyler Brantley, 359th MDG bioenvironmental
technician.
Brantley said that readings are taken continuously,
especially during the “101 Critical Days of Summer” where 91 degrees
Fahrenheit, based on the WBGT reading, occurs daily and is a black flag
condition.
The 101 Critical Days of Summer traditionally begins the
Memorial Day weekend and ends Labor Day weekend and supports commands’ focus on
safety in hot weather.
“Each flag category has work-rest cycles and everyone has to
have thermal stress training if they work outside,” Brantley said, adding that
training is familiarizing personnel with the WGBT work-rest cycles and fluid
intake requirements.
At JBSA-Randolph, flags are flown on the flight line and at
the fitness centers as well as any place people are working outside as well as
near unventilated hangars.
“You’re basically outside because those hangars can get
really hot,” Brantley explained. “Some people have the black pirate flag flying
– the Jolly Roger – in place of the regular black flag, it’s pretty funny.”
“JBSA-Fort Sam Houston relies on command post information
for WBGT readings and flag conditions,” explained Mark
Magalski, chief of 502nd Air Base Wing Operations, “but units training
downrange at JBSA-Camp Bullis are required to take their own readings.”
Safety is paramount for JBSA personnel, Montoya said,
stressing that heat accidents are preventable and ensuring everyone is aware
gives commanders another tool to ensure the safety of their people.