It's summer, and a hot one at that, and just about everybody has reason to worry about the effects of heat on their bodies. So what are strategies you and your workplace can employ to try and avoid heat-related health problems? Let's go over some of the information you'll need, and some solutions.
What is heat stress/strain?
According to Dr Ross Di Corleto on the 3M Science of Safety podcast, heat stress "is the environment ... the heat, the humidity, how hard the individual is working, what they're wearing, their clothing. Now, individually and combined, these things create a heat stress on the body." Heat strain, on the other hand, is "how the body responds to those stresses". Heat stress is what you measure, and heat strain is how you react.
How does your body cool you down?
As most people would be able to guess, sweating is your body's way of cooling you down. Your blood actually carries the heat from inside of you to your skin, where it is transferred out of the skin through the sweat, meaning as the sweat evaporates, the heat goes with it - cooling you down.
Heat-related illnesses/symptoms:
There are a diverse range of impacts that excess heat has on the body. There are the obvious ones, of course - heat stroke, fainting, etc. However, these are the severe, late-term symptoms. The earlier symptoms can oftentimes be much more discreet.
For example, some of the first symptoms can actually be fatigue and lethargy - the unwillingness to do anything on a hot day we all know far too well. Being worn out and tired can very easily be a symptom of dehydration, and heat-related problems. This often results in reduced performance. European studies found that for every degree above 25°C, workers lose 2% productivity. At 35°C, there is approximately a 20% loss of productivity, a significant and impactful decrease for any workplace.
With this comes a deterioration of cognitive function and mental fortitude, broken concentration and trouble focusing. This alone is a hazard - safety incidents become more frequent during hotter parts of the year, likely a direct result of these effects.
It's only beyond this point that you get to the more severe symptoms - cramps, heat rash, heat stroke, death. There are also some reports of chronic heat-related problems - kidney problems, liver problems, heart problems, etc, from people who spend a lot of time working in hot environments. So even if you've never fainted from the heat, or even had anything as severe as cramps, you could potentially be at risk for problems in the future if you aren't careful about your heat stress.
Am I at risk?
Yes.
Risk levels for individuals can vary on many different factors - fitness, age, fluid intake, drug use (alcohol, prescription, or illicit), acclimatisation, and so forth. However, unless you're from space, every person has at least some reason to be aware of the heat and its effects on them, so be careful.
How much water do I need?
The answer to this, typically, should just be "more". It is not as simple as stating an amount of water and leaving it at that. Dr Ross Di Cortelo says "fluid replacement should try to approximate the sweat and urine losses." A very general recommendation is 200-300mL every 10-20 minutes, but this is far from a hard rule. If you're thirsty, you should drink until you aren't anymore - and then you should have some more. Thirst is a symptom of dehydration, meaning that if you ever get thirsty, you're technically not having as much water as you need. This isn't anything to stress about, but it's something to keep in mind as you regulate your fluid intake.
What can I do about this?
There are a lot of different ways to manage heat stress. Hydration and Cooling is an entire category of its own on our site, with a lot of different effective options worth checking out. For the very simple control measures, there are water bottles and water coolers - a staple of most workplaces.
For personal attire, there are cooling caps and cooling vests that can be worn for relief and cooling.
You can even improve on the fluid you drink - adding some electrolyte replacement drinks or some Sqwincher Squeeze Pop Ice Blocks can be a valuable way of replacing the body salts lost through sweat, as well as giving you a tasty improvement on water.
The most important thing you can do, however, is be aware of the symptoms and risks. All the risk prevention in the world won't help you if you don't realise you need a drink. Don't push yourself beyond your limits.
For further details, view the two part 3M Science of Safety podcast episodes on this important topic
