Articles, Blog

Heat Related Illness (2013 Refresher)

January 18, 2020

The excessive heat is our big story at six,
firefighters having a hard time battling the rising temperatures. On the frontlines
of that fire yesterday, when he collapsed, likely as a result of heat exhaustion. Crews say the heat is another factor slowing them down. Firefighters did go to the
hospital with heat exhaustion and smoke inhalation, but imagine fighting a fire in triple-digit temperatures
and wearing all that gear. It’s fire proof, heavy, but the material
doesn’t breathe well, that adds to your body’s heat. He was in tip-top physical condition
but he died of heatstroke on the fire line. All the effects come down on them at the
same time, the adrenaline is pumping, they’re fighting fire, the heat, a combination of
many things. We went down to Texas the end of July, the
beginning of August, it was about midway, getting into the last third of fire season. We’d been busy up to that point, we’d been
down to Southern Arizona, and we’d been in the high country of Colorado, so a wide range
of different fuel types and conditions. Our first night in Texas, everyone described
it as kind of oppressive heat, just that really high heat with humidity. The fires in Texas had been going on for,
it seemed like, most of the summer, so we’d been getting a lot of information, we saw
some warnings about the high heat, fuel types, fire activity, things like that and that was after
the fatality incident, so there was a lot going on to that respect, so awareness was
high on heat illness, and extreme heat in Texas at the time, and it was running and
gunning from the get go, it was busy. Basic human physiology suggests that heat
production is a function of metabolic activity. The more active the skeletal muscle is, the
more heat production that individual has to figure out how to off-load to the environment. So when the environment is pressing down on
you, or pressing back on you because the temperature of the sun, and the ambient conditions are
quite warm, or the temperatures associated with the fire, that radiant heat from the
fire, get to be pretty demanding, those add to the stress. It doesn’t mean that a person can’t develop
heat cramps, heat exhaustion, or issues in cooler environments. If their work output is so aggressive, or
aggressive enough to cause an elevated core temperature, and even in cooler ambient environments,
they can’t off-load it quick enough, they could suffer from a heat-related injury. I started noticing that line production was
decreasing, particularly in the heat of the day ,in the late afternoon, and when I observed
my most fit, hardest working firefighters going down really quick, in that environment,
that’s when I knew it truly was not business as usual. That was kind of I think the seed, of trying
to figure out what was going on, in that something beyond whatever those frustrations were, beyond
the crew just not producing, it wasn’t through lack of effort, or lack of ethic, the physiological
was kicking in, the heat illnesses was kicking in, that environment was knocking back our
production. Most of the issues that firefighters are going
to face is going to be due to an exertional heat stress. So, they’re working hard, in an aggressive
environment, the muscle contraction that happens over and over and over as the person’s line
digging or hiking aggressively, or whatever, as that metabolic heat production escalates,
the core body temperature starts to run upwards. And when it gets to a critical level, and
that’s going to be different for every individual, there’s a lot of individual variability,
then the person might start to develop those cramps. Heat cramps can happen as a result of an electrolyte
imbalance, or it could just be a slight drop in hydration, or it could just be an irregular
rise in core temperature. It’s really hard to pinpoint what the precise
mechanism is. But when those happen, they function as an
early warning sign to say, hey, wait a minute, something is not right here. Let’s get you out of this heat, get that
fire shirt off you. He said earlier that his hands were cramping up too. If they don’t address those symptoms, guaranteed
heat exhaustion’s going to enter into the picture. When a person starts to experience heat exhaustion,
certain telltale signs are always present. So, usually it’s dizziness, usually it’s
fatigue. It’s usually associated with and most often
associated with a feeling of overwhelmed, the body’s just overwhelmed with heat. Everybody on the crew experienced at least
mild heat illness once or several times throughout the course of the assignment. Those early symptoms of headache, nausea,
light headedness, some cramping. Everybody experienced that while we were down
there, across the board. Some of the most severe effects occurred with
our sawyers, certainly with the amount of work they’re doing, the extra layers they’re
wearing I think contributed to that. The common approach to treating heat exhaustion,
at least it seems, in the military and the fire agencies, is to address it with aggressive
hydration. And that is, again, secondary to what really
needs to happen. And so cooling the individual is really the
primary course of treatment. We got to get you out of the heat, dude. Keeping you in the sun ís not helping. Getting them to stop work, which they’re
probably going to voluntarily do, because they’re going to collapse, or they’re just
going to complain to the point that they’re going to need to stop. So getting them in the shade, cooling them
off with external cooling, and then, down the line, addressing any hydration issues
that may need to be addressed. If they continue to ignore those symptoms,
then it can progress almost instantly from heat exhaustion to heat stroke. And at that point then, helicopters got
to get involved, medivacs going to be the case, and then a whole lot of other individuals
are put at risk. So you need to get that person off of the
site immediately, cool them down rapidly. But the only way you’re really going to know,
is this heat exhaustion? Is this heat stroke? That’s not really the argument that you need
to have on the mountain. That’s an argument that’s reserved for the
clinical environment. And the only way you’re going to know is
if you have a good solid measure of core body temperature. We really relied on our EMT to make judgments
for us, to trigger an EMS response. We did rely on personal assessment of those
early signs, though. We wanted folks to be honest with themselves,
and if they weren’t feeling so good to speak up about it, to either tell their buddy, tell
their leader, tell me. And I said it over and over and over again,
because it is somewhat against our natural culture. And I think the reason why is it can be perceived,
or sometimes perceived, as a weakness. And in that situation the thought had nothing
to do with fitness, strength, motivation, work ethic, it was a physiological issue. Our mission is to suppress fires, given whatever
objectives are given to us, employ the best tactics to achieve those objectives. We’re a production oriented culture, and
we’re given a mission, we want to do it as best we can, as fast as we can, as good as
we can. And taking breaks will naturally detract from
your line production, from the speed at which you accomplish your tactical objectives. So, those are counter-intuitive. But the bottom line that we saw, was that
we could produce more line if we gave the crew members more frequent breaks as it got
hotter. You have some conflicts. Number one, you want to take care of the folks
working for you, but you have objectives that you want to achieve as well, and so you have
to find a balance. How can I take care of my folks while still
achieving the objectives and perform excellent work? And so, going through some of those experiences
we started changing our tactics. We came up with some ideas of how to take
the breaks, and kind of a more formalized approach to it, utilizing temperature charts
and some ideas that we’d seen from the military, and coming up with a work/rest ratio based on escalating
temperature, where it broke it down into a few categories. And when we’d hit those temperature trigger
points, it resulted in us taking set breaks, work/rest ratios. There’s no scale that you can calibrate that’s
going to be more effective than a really experienced crew supervisor. That they know what that crew can tolerate
and what they should tolerate, and to be conservative in the work/rest that’s necessary. A bi-modal shift, as I saw it, as it related
to that incident, would be just focusing work production, focusing line suppression efforts
in the mornings, say 0600 to 1400, and then through 1400 to 1800, or pull back to patrol,
monitoring, like we were doing in the work/rest ratio, where it involved refurb, active patrol
of the line we put in, as well as scouting line that we’re going to put in later, responding
to any kind of flare-ups, spot fires, any kind of needs around the fire. And then in the evenings pick it back up as
temperatures started to drop back down. Get back on the line and continue with line
construction. It may not work in all situations. It’s likely not to work in every situation. So some things that can be barriers are travel
times, as well as any logistical needs, if you’re needing to pick up food or water,
things like that. There’s so many different variables, but
the shorter that we can make the briefings, the quicker we can get to the line, and the
better we’re able to utilize the more mild conditions. You know, the animals have figured it out. Desert animals are active in the mornings
and evenings, and shade up during the heat of the day. It’s about being more efficient with your
energy. That would be awesome if we’d be able to
predict who was going to go down before they went down, so we could address it ahead of
time. What happens though, if somebody goes down
from a heat-related illness, the likelihood of a subsequent one is higher. Right now, we have data from other projects
that strongly suggests that the biggest protection against the potential development of a heat
illness, especially in a group of 20 people on a crew, the individuals that have the highest
aerobic fitness level, they’re going to have the best possible protection. So, of the different categories that puts
a person at risk for heat-related injury, certainly aerobic fitness is the highest. And then whether or not the individual has
had a previous illness is another predictive factor. Hydration status of the individual I suppose
is somewhat linked, but it’s really difficult to evaluate accurately an individual’s hydration
status. The worst practice that you can do is to drink
exclusively an overabundance of plain water. That’s going to do you a disservice, and
that’s more dangerous than not drinking an adequate amount of fluids. Nowadays we think of that as hyponatremia,
when the blood sodium, drops below critical values, so have some sport drinks always on
hand, have electrolytes in the foods that you have, and use those during the especially
aggressive periods of work, when the sweat rate is at its highest. The idea of cumulative exposure may work in
their favor, in terms of assisting them to develop some of the physiological characteristics
that are associated with heat acclimatization. It really had more to do with the amount of
exertion that they were expelling. Acclimation really didn’t, it helped. I think it provided some more resilience to
the heat illness, but if folks were working hard, and it was hot, symptoms arose. In a given 14 day cycle, if they’re not given
an adequate work/rest ratio here and there, and their diet ís not very great and their
sleep ís not very great, which certainly sounds like most 14 day assignments, then that could
increase their risk during that window of time, but don’t use segments of the fire
season to train for the future fire season. You want to show up fit for duty. That includes being aerobically fit to tolerate
the work, and also to tolerate some of the environmental concerns. As a Hot Shot crew, assigned to west Texas
IA at that time, after a fatality occurred, it was not lost on us that we were a Hot Shot
crew doing the same exact thing, in the same exact place, at the same time, that resulted
in a fatality. So I drove home the point that we were in
a serious condition, a serious environment, with extremely serious consequences. And so that facilitated us really taking a
look at how we were doing business, and how we might change it to make sure that we did
everything possible to keep the crew safe. I think, overall, it ís really more about
just being willing and able to recognize that you’re in a situation that requires some
different tactics. So you need to recognize that you’re in a
potentially dangerous situation, learn about it, and adapt to it. And that will be different in every kind of
situation. It may not be heat, it may be something else. So I think it’s imperative on everyone that’s
on the line to be able to, and be willing to, and strive to assess the situation, recognize
it, and figure out a way to deal with it.


  • Reply lynnette hamm June 27, 2013 at 8:23 pm

    Please take this to heart! For more info, see the NIOSH recommendations as well. Go home safe to your family. Watch over one another!

    Caleb's mother

  • Reply Andrea Patane December 20, 2014 at 6:30 pm

    Heat related illnesses aren't laughing matters.

  • Reply Lynnette Hamm May 18, 2017 at 4:00 am

    Caleb Hamm died because he was left alone after telling others he felt ill. He was left alone to stumble and fall into a ravine. Wasn't found till later, by then he was dying. These ideas aren't worth a hoot unless you trust your crew to help you. Caleb's crew apparently didn't deserve his trust did they? But don't take my word, read the SAIR the BLM put out. Sent it by email to me, didn't even bother to sit down with me, just showed up in my email one day. Yes that is how they handle it. No one would even answer my questions to this day they ignore me won't respond act as if my questions don't deserve answers.

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