Minimize accidents & health risks. Provide an instant read WBGT Wet Bulb Globe Temperature Heat Index Monitor on site.
Heat Stress leads to Heat Stroke and kills indiscriminately. Anyone is at risk when the body is unable to cool down quickly enough. This is common with strenuous activities in high heat & humidity and increases substantially when combined with the radiant heat of the sun & dehydration. By the time you, feel thirsty you may already be dehydrated.
Operations involving radiant heat sources, direct physical contact with hot objects, or strenuous physical activities (when there is an inadequate tolerance) have a high potential for inducing heat stress when combined with high humidity and air temperatures. Such places include: iron and steel foundries, nonferrous foundries, brick-firing and ceramic plants, glass products facilities, rubber products factories, electrical utilities (particularly boiler rooms), bakeries, confectioneries, commercial kitchens, laundries, food canneries, chemical plants, mining sites, smelters, and steam tunnels.
Outdoor operations conducted in hot weather, such as athletic training, hiking, construction, refining, asbestos removal, and hazardous waste site activities, especially those that require workers to wear semipermeable or impermeable protective clothing, are also likely to cause heat stress among exposed workers. Additionally some medications or even a ‘hang-over’ can be factors that contribute.
Heat Stress occurs when the heat is absorbed from the environment quicker than the body can cool itself back down. It is important that our bodies maintain a consistent internal temperature. The body typically will regulate the heat through evaporation of sweat and by changing the blood flow to the skin. Once the body gets a little behind in the cooling process (typically over 100° F) the heat begins to defeat the brain’s ability to keep up. Subsequently there is a higher risk of accidents and physical symptoms begin to occur.
Heat Stress is the pathway to a far more serious condition called Heat Stroke. Heat Stroke can be fatal, however the body will go through several different stages of heat illnesses before reaching a Heat Stroke.
- Heat Stress: begin to sweat, body feels hot; body temperature stays normal (approximately 98.6° F).
- Heat Fatigue: muscle weakness, headache, thirsty, skin feels cool and moist body temperature stays normal.
- Heat Syncope: slight dizziness or faint feeling, skin may be pale, heavy sweating, but skin feels moist and cool; body temperature stays normal.
- Heat Cramps (serious): muscles in legs and arms hurt a lot, pain in abdomen, skin feels moist and cool; body temperature rises, but is still in the normal range.
- Heat Exhaustion (dangerous): thirsty, giddy, weak, uncoordinated, or nauseous; heavy sweating, skin is cold and clammy; body temperature rises, but is still in the normal range.
- Heat Stroke (life-threatening): skin is dry and red, sweating has stopped. Staggering, confusion, fainting, rapid pulse; body temperature rises above 104° F.
Prevention:
- Prevent dehydration. Drink lots of water; at least 1 cup every 15 minutes is a basic guideline. That is 16 ounces every half hour or 1 gallon for an 8 hour workday. The internal thirst meter is not responsive enough when you need that much water (typically by the time you feel thirsty, you may already be dehydrated), so keep drinking the water regardless of how thirsty you feel.
- Avoid alcohol. Even though its a liquid, alcohol dehydrates the body more and decreases the body’s ability to cool.
- Avoid high sugar, heavy meals and caffeine.
- Block out direct sun or other heat sources when possible.
- Set up a shade station and rest regularly out of the direct sun. Provide a manual or powered fan, misting bottle and clean, fresh cool water. Don’t forget the first aid pack.
- Know signs & symptoms of heat related illnesses; monitor yourself and coworkers regularly.
- Wear lightweight, light colored, loose-fitting clothes. A wide brimmed lightweight hat with vents (consider fabrics that breathe well & offer UV protection).
- Provide an easy method to measure Heat Index on site. More info
OSHA Heat Stress Quick Card (PDF format)
