No matter what we put them through or how we maintain them, our bodies work amazingly well. And because they function only at a narrow range of temperatures, they have ways to control heat.
Work environments can challenge that ability to maintaining a low (or high) enough temperature. When hot conditions cause even our heat-regulation itself to break down, a downward spiral can land us in OSHA’s database of work-related deaths.
How we cool down
We have two main strategies for keeping cool. One is pumping hot blood to surface of the skin to be air-cooled, and the other is evaporation, in other words sweating.
The closer the air temperature is to our body temperature of around 98.6 F, the less easily we can get rid of heat by pumping blood or sweating, especially when it’s humid.
Also, remember that sweating uses up water and salts, so we need to keep supplying ourselves with those ingredients or our cooling and other systems may fail.
When cooling fails
When we’re too hot, our body tries to do something about it. Our heart pumps faster and our blood vessels get wider to help get more hot blood to our skin. Both make our work harder, often moving 2 to 4 times as much blood per minute than normal.
The salt and other minerals we lose when we sweat are needed for other uses, too. Our entire nervous system, including our brain, needs them for sending information and our muscles use them every time they move. In fact when salts and other minerals get too low, our body snaps into action to hold on to them. That’s why people suffering heat stress typically stop sweating, which only makes things worse.
The combination of wide-open blood vessels and the loss of brain-firing minerals stops our brain from working well. You may become irritable, unable to focus on anything, unwilling to drink fluids, and become sick and faint. Death isn’t especially uncommon, and it can be quick and very surprising to coworkers.
How to prevent heat illnesses
Safe working conditions in warm weather are the most important answer. Good air conditioning, ventilation and fans can work wonders. Plenty of drinking water is critical and cycles of work and rest are important. Also, we get better at tolerating heat and cold with practice, so newer workers may need time get used to working in the heat. The time may vary with physical condition, age and experience.
Most importantly, take heat-related illness very seriously. Notice how you feel and look for signs of illness in others. If there are warning signs, act immediately.