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After the cool temperatures of spring slowly pass, the energy draining temperatures of summer are ready to descend on us. For anyone working outdoors, or work in heat-producing environments, heat is not only uncomfortable, but it can also be very dangerous.
Heat related sickness affects thousands of workers every year and more than 40 have lost their lives because of it. Unfortunately, about half of these deaths occur in the construction industry. Heat can make anyone sick, but people, who are overweight, have high blood pressure or heart disease are at increased risk. So is anyone who takes allergy medication, decongestants or blood pressure medication.
Heat stress can induce a series conditions and illnesses ranging from rashes and cramps to heat exhaustion and life-threatening heat stroke. However, construction laborers are particularly vulnerable to heat stress and illnesses because of the heavy climates they work in.
Why is heat a hazard to workers?
When working in a hot environment, the body must get rid of excess heat to maintain its stable internal temperature. It is able to do this by circulating blood to the skin and through sweating.
If the air temperature is close to or warmer than normal body temperature, the process of cooling of the body becomes more difficult and the blood that is circulated to the skin cannot lose its heat. Thus, sweating becomes the main way the body cools off. However, sweating is only effective if the humidity level is low enough to allow evaporation, and if the fluids and salts that are lost are adequately replenished.
Remember, if the body cannot get rid of excess heat, it will then store it. When this happens, the body’s core temperature rises and the heart rate will also increase. As the body continues to store heat, the person will begin to lose concentration and will have difficulty focusing on a task, may become irritable or sick, and many times will lose the desire to drink. The next stage is most often fainting and even death if the person is not cooled down.
How to know when it’s too hot:
- Temperature rises
- Humidity increases
- The sun gets stronger
- There is no air movement
- No controls in place to reduce the heat imitated from equipment that radiates heat.
- Protective clothing is work
- Over all work is strenuous in nature.
Symptoms Heat Illness:
- Working in high temperatures and humidity, direct sun exposure and no breeze
- Engaging in heavy physical labor
- Wearing waterproof clothing
Symptoms of Heat Exhaustion:
- Headaches, dizziness, light-headedness, fainting
- Weakness and moist skin
- Irritability or confusion
- Upset stomach, vomiting
Symptoms of Heat stroke:
- Dry, hot skin with no sweating
- Confusion, loss of consciousness
- Seizures or convulsions
What can you do to help prevent and protect workers from Heat Stress?
By following a few precautions you can help prevent Heat Stress
- Know signs/symptoms of heat illness; monitor yourself; use a buddy system.
- Gradually increase workloads and allow more frequent breaks for workers new to the heat or those that have been away from work to adapt to working in the heat (acclimatization).
- Provide cool water to drink (five to seven ounces) every 15 minutes.
- Require rest breaks in a cool, shady spot and with fans available.
- Schedule heavy work during the coolest time of the day.
- When possible, assign work that can be done in the shade.
- Rotate workers when working in the heat is unavoidable.
- Suggest workers wear lightweight, light-color clothing.
- Schedule additional rest breaks for workers who wear protective clothing and check their temperature and heart rate.
If a worker has symptoms of heat stroke:
- Call 911
- Move him/ her into shade
- Provide cool drinking water, if able to drink
- Wipe skin with cool water
- Loosen Clothing
- Fan with cardboard or other material
Working in extreme heat is many times unavoidable when working in construction; however it doesn’t have to be unendurable. With preemptive planning, proper training and investment in cooling systems for workers, construction laborers can work safely when temperatures are high.
Additional Resources for Information on Heat Stress
If you are looking for additional resources on Occupational Heat Exposure there are two specific ones that we recommend.
The OSHA NIOSH Heat Stress Tool is a free app for your mobile devices. This app allows you to calculate the heat index for your work site (yes, it is GPS enabled so your information is specific to your actual project) and based on the heat index will display the risk level to the employees that are required to work in the environment. With a simple click you can get reminders about the protective measures that should be taken at that risk level to adequately protect the worker.
CPWR also provides additional training materials from OSHA, NIOSH, as well as materials they have created. (Working in Hot Weather)