Working in warm to hot conditions is a serious safety concern. Thousands of workers become sick every year from exposure to heat. Some even die. Heat illnesses and death are preventable if you learn to identify the warning signs and take the appropriate action.
Heat stress is the general term used to describe heat-generated illnesses that result when the body is unable to cool itself through sweating.
10 Safety Tips for Working in the Heat
- Stay hydrated. Drink plenty of fluids; drink about 450-500 ml before starting and 150 ml every 15 or 20 minutes. Don’t wait until you’re thirsty – your body is sweating (perspiring) out fluids and you have to keep replacing it. Water is the best thing to drink.
- Avoid dehydrating liquids. Alcohol, coffee, tea and caffeinated soft drinks can hurt more than help.
- Wear protective clothing. Lightweight, light-coloured and loose-fitting clothing helps protect against heat. Change clothing if it gets completely saturated.
- Pace yourself. Slow down and work at an even pace. Know your own limits and ability to work safely in heat.
- Schedule frequent breaks. Take time for rest periods and water breaks in a shaded or air conditioned area.
- Use a damp cloth. Wipe your face or put it around your neck.
- Avoid getting sunburn. Use sunscreen and wear a hat if working outside.
- Be alert to signs of heat-related illness. Know what to look for and check on other workers that might be at high risk.
- Avoid direct sun. Find shade or block out the sun if possible.
- Eat smaller meals. Eat fruits high in fibre and natural juice. Avoid high protein foods.
Preventing Heat Illnesses
The best form of protection is prevention. Employers should establish a complete heat illness prevention program, which includes provisions for providing workers with water, rest and shade; modified work schedules as necessary; planning for emergencies along with training for workers about the symptoms of heat-related illnesses and their prevention; and monitoring workers for signs of illness.
Other strategies to protect from a heat-related illness include:
- Drink water every 15 minutes, even if you are not thirsty. [Check the colour of your urine – if it is dark yellow to brown, get some water into your body as soon as possible!]
- Rest in the shade to cool down [Working in full sunlight can increase heat index values by 100C. Keep this in mind and plan additional precautions for working in these conditions.
- Wear a hat and light-coloured clothing – slip (on a shirt) – slop (on some sunscreen) – slap (on a hat).
- “Easy does it” on your first days of work in the heat. You need to get used to it.
- Eat a regular, well-balanced diet. Try to stay away from hot or heavy foods.
- Be aware that water, concrete, and sand reflect the sun and can make it stronger.
Identifying Heat Illnesses
There are basically four types of heat illnesses. In increasing severity, they are:
||Skin irritations usually caused by excessive sweating; rather minor, easily treatable, and recovery is generally quick|
||Muscle pains or spasms that can happen during periods of overexertion; rather minor, easily treatable, and recovery is generally quick|
||Symptoms include heavy sweating, rapid breathing, and a fast, weak pulse. Although heat exhaustion is not as serious as heatstroke, if it goes untreated, it will lead to heatstroke.|
||Heat stroke is the most serious heat-related disorder and occurs when the body can no longer control its temperature. The body temperature can rise to 410C (1060F) or higher within 10 to 15 minutes and heat stroke can cause death or permanent disability if emergency treatment is not provided.
Symptoms include dry skin, rapid, strong pulse, and dizziness. Heatstroke is life-threatening.
Heat illness can strike any employee whether they work inside or outside. However, workers exposed to hot and humid conditions are at a greater risk, especially those doing heavy work tasks or using bulky protective clothing and equipment. This risk can be increased even more for some if they have not built up a tolerance to hot conditions, including new workers, temporary workers, or those returning to work after a week or more off. All workers can be considered at risk during a heat wave.
Workers at greater risk of heat stress include those who are 65 years of age or older, are overweight, have heart disease or high blood pressure, or take medications that may be affected by extreme heat.” Basically, if you work or play in a hot environment you are at risk of heat stress.
As some workers are at greater risk of heat illness, certain industries have a higher rate of employees experiencing heat-related illness. Examples include construction; trade, transportation and utilities; agriculture; building and grounds maintenance; and landscaping services.
Heat Illness: Symptoms and Prevention
Heat stroke occurs when the body no longer sweats and body temperature reaches dangerous levels. Symptoms of heat stroke include:
- Dry, hot reddish skin and lack of sweating
- High body temperature
- Strong, rapid pulse
- Slurred speech
Heat exhaustion is the body’s response to the loss of water and salt, typically through sweating. Symptoms of heat exhaustion include:
- Excessive sweating
- Weakness or fatigue
- Dizziness and/or confusion
- Clammy skin
- Muscle cramps
- Flushed complexion
Heat cramps are painful cramps in the body’s muscles due to low salt levels and are typically caused by excessive sweating. Symptoms of heat cramps include:
- Muscle pain usually in the abdomen, arm or legs.
- Muscle spasms usually in the abdomen, arm or legs.
Heat Rash is an irritation of the skin caused by excessive sweating. Symptoms of heat rash include:
- Red cluster of pimples or small blisters
- Usually on neck and upper chest, groin area, under the breasts, and in elbow creases.
Best Practices for Working in Heat
The best defence we have for preventing heat stress is proper work practices and training. Implement these best work practices:
- Limit time in a hot environment.
- Take frequent breaks in a cool environment.
- Drink plenty of cool water or non-caffeinated beverages.
- Acclimatise employees to hot conditions over 7 to 14 days.
- Train employees to recognize the signs and symptoms of heat related illnesses.
- Train employees on first aid procedures and when it’s time to contact emergency medical services.
- Train employees on the causes of heat related illnesses and ways to minimize these causes.
Heat Safety Resources
Safe Work Australia (SWA) has several good resources available, including print documents and broadcasts. CLICK HERE.
CLICK HERE to download the Safe Work Australia ‘Guide for managing the risks of working in heat’.
Related SWA materials
- First aid for heat-related illness
- Checklist for risk-managing heat in the workplace
- Code of practice: Managing the Work Environment and Facilities
- Code of practice: Work health and safety consultation, co-operation and co-ordination
- Code of practice: How to manage work health and safety risks
- Code of practice: First aid in the workplace
- Guidance material: Guide on exposure to solar ultraviolet radiation
- Bureau of Meteorology’s Heatwave Service for Australia
Click here to download the heat stress basic calculator from Workplace Health and Safety Queensland.
The U.S. Department of Labor (DOL), Occupational Safety and Health Administration (OSHA), National Institute for Occupational Safety and Health (NIOSH) and the Centers for Disease Control and Prevention (CDC) have some valuable resources to address these concerns. For more information about safety while working in the heat, see OSHA’s heat illness webpage, including online guidance about using the heat index to protect workers.
They also have developed a free heat safety app for Android and iPhone that allows users to enter the current temperature (in 0F ) and humidity. It will calculate the heat index and provide a risk level. You can then select “precautions” and it will give you a list of what you can do based on the current risk level. [Note: there are some issues with accessing local Australian weather data.)
The App allows workers and supervisors to calculate the heat index for their worksite, and, based on the heat index, displays a risk level to outdoor workers. Then, with a simple “click,” you can get reminders about the protective measures that should be taken at that risk level to protect workers from heat-related illness-reminders about drinking enough fluids, scheduling rest breaks, planning for and knowing what to do in an emergency, adjusting work operations, gradually building up the workload for new workers, training on heat illness signs and symptoms, and monitoring each other for signs and symptoms of heat-related illness.