Temperature Extremes
A change in body temperatures due to extreme work environmental conditions can lead to stress or illness from heat and cold. If not treated in time, both heat and cold stress can develop into life-threatening situations.
- Heavy work in high temperatures can cause muscle cramps, dehydration, sudden collapse, and unconsciousness.
- Cold temperatures can lead to fatigue, irregular breathing, confusion, and loss of consciousness (hypothermia).
The table below shows some common heat and cold injuries on a construction site.
| Heat Illnesses | Cold Illnesses/Injuries |
| Heat Rash | Frost Nip |
| Fainting | Immersion injury (Trench Foot) |
| Heat Exhaustion | Frostbite |
| Heat Stroke | Hypothermia |
| Heat Cramps |
Hot Working Conditions
The following conditions can occur if a worker is exposed to hot temperatures:
Heat exhaustion – can result in headaches, dizziness, light-headedness, weakness, mood changes, feeling sick to your stomach, pale clammy skin, vomiting, and fainting.
Heatstroke – leads to dry, pale skin, mood changes, seizure, collapse, and possible death.
Follow these safe work practices when working in hot temperature conditions.
- Seek medical help for cold- and heat-related stresses.
- Lower the employee’s body temperature in heat-related conditions.
- Perform work during cooler times of the day.
- Use the “buddy” system (work in pairs).
- Drink plenty of cool water in warm, hot weather.
- Wear appropriate clothing (hat and light, loose-fitting, breathable clothing).
- Apply sunscreen on sunny days.
- Take frequent, short breaks indoors to cool off.
- Educate employees to recognize and seek medical help for workers that have symptoms of heat-related stresses.
Cold Working Conditions
Cold working conditions can also cause problems for construction workers. For example, rain, snow, sleet, and other wet and windy conditions can be unbearable for extended periods of time.
The following conditions can occur if a worker is exposed to cold temperatures:
- Frostbite is the freezing of deep skin tissue layers and leads to hardening and numbing of the skin. It usually affects the fingers, hands, toes, feet, ears, and nose.
- Hypothermia occurs when the body’s temperature falls below 95 degrees F. The person becomes tired and drowsy, begins to shiver uncontrollably, moves clumsily, and is irritable and confused. As the hypothermia progresses, the victim’s speech becomes slurred, his or her behavior may become irrational, and unconsciousness and full heart failure can occur.
Follow these safe work practices when working in cold temperature conditions.
- Seek medical help for cold-related stresses.
- Raise the employee’s body temperature in cold-related conditions to prevent the progression of symptoms.
- Schedule work during appropriate times of the day.
- Perform work during the warmer times of the day.
- Use the “buddy” system (work in pairs).
- Do not drink alcoholic beverages in cold weather.
- Drink warm beverages in cold weather.
- Wear appropriate clothing (warm, layered clothing, including hat and gloves). Pay special attention to protecting feet, hands, face, and head. Up to 40 percent of body heat can be lost when the head is exposed.
- Take frequent, short breaks to warm up.
- Avoid exhaustion or overworking, because energy is needed to keep muscles warm.
- Educate employees to recognize and seek medical help for workers that have symptoms of cold-related stresses.
