Heat illnesses are preventable but if left unchecked can lead to death. Anyone working in the sun will find this site’s information critical to learn for themselves and their coworkers.
Four Types of Heat Illness
Heat Cramps. Athletes are familiar with this syndrome caused by salt depletion. It is easily treated with rest and drinking electrolyte-balanced fluids such as sports drinks or plain water and eat salty chips or nuts. Avoid salt tablets due to the risks of overdosing.
Heat Syncope/Fainting. Fainting happens when blood pools in the legs, often after standing too long. It is temporary; being horizontal usually prompts a return to consciousness. The biggest risk is an injury from falling. To help blood return to the heart, elevate the person’s legs, and cool the body with wet compresses and fanning. Turn the unconscious person on his or her side to prevent choking. One exception is if the person has been working hard; then consider the fainting due to heat stroke and call 911. Check the ABCs (airway, breathing and circulation) and cool him or her down immediately. Anyone who faints should be medically evaluated and not return to work.
Heat Exhaustion. This condition is serious and is caused by severe dehydration. Symptoms can include fatigue, dizziness, nausea and vomiting, plus early neurological signs such as headache, impaired judgment and anxiety. Exhaustion causes profuse sweating and cool, clammy skin. Move the person out of the heat, provide fluids as tolerated, strip off extra clothing, and cool them by wetting clothing and fanning. Have them medically evaluated.
Heat Stroke. This is a medical emergency. It can look like exhaustion except the body temperature is 104 degrees F or higher, and the brain is seriously affected. Neurological effects can include confusion, irrational or aggressive behavior, incoherent speech, collapse, convulsion, and coma. When the body’s heat-coping mechanisms have failed, sweating stops and the skin becomes red, dry and hot to the touch. Call 911 and quickly lower the body temperature.
Identification & Treatment
Learn to recognize heat-related illnesses. Identifying and responding to early symptoms can save lives. Encourage a buddy system for remote work locations.
Three Steps for Heat Illness Prevention
Hydration is the most important step to combating heat stress. In extreme heat and humidity, workers should use the half-half rule: drink ½ liter every ½ hour. Workers should not wait until they feel thirsty to drink; if they are thirsty, they may already have lost 2% of their body’s water. The onset of heat exhaustion can begin after losing 3% of the body’s water and heat stroke occurs once 8% is lost. The bottom line is, if a worker is not regularly urinating or has dark urine, they are dehydrated and at risk for heat illnesses!
Assess the relative danger of the CONDITIONS and your PERSONAL risk factors.
Conditions: Be aware that high heat, high humidity, low air circulation all create a more dangerous working environment. When more than one of these variables is present, the danger is compounded. In these conditions, workers need to take breaks in the shade and wear light, breathable clothing and hats. Some farmworkers wear excess clothing to protect themselves from the sun, but this is a dangerous practice that has resulted in a local death. Take the Personal Risk-Factors Self-Assessment questionnaire listed under resources (below) to determine additional risk.
If an employee is new to a job or is returning after time away: ease them back into full-time work over the course of 5 days. Starting workers at half-time or 50% effort and increasing to a full-time work load (by 10% each day) can greatly reduce the employee’s susceptibility to heat stress.
- NEW VIDEO! "Working in the Heat Novellas, Awareness, Response, and Prevention for Heat Illness" (Spanish with English subtitles)
Bilingual transcripts are also available.
- Heat Illness Types - shown in graphics (English and Spanish)
- Quick Reference Table, "Heat Illness - Know the Signs and Dangers" (English or Spanish)
- Signs and Symptoms Body Map (English and Spanish)
- Work-related and Weather Causes (English and Spanish)
- Personal Risk Factors Self-assessment Questionnaire (English or Spanish)
- Prevention Information (English and Spanish)
- Heat Stress Jeopardy PPT (English or Spanish)
Articles & Useful Links
- 'Humidex' ID's which Hot Days Pose Most Peril IN King County, UW Health Sciences NewsBeat May 2015
- Increased Mortality Associated with Extreme-heat Exposure in King County, WA, 1980-2010, International Journal of Biometeorology May 2015
- Increased Hospital Admissions Associated with Extreme-heat Exposure in King County, WA, 1990-2010, Reviews on Environmental Health March 2015
- Outdoor Heat Exposure Rule, Washington Department of Labor & Industries
- Outdoor Heat Exposure - Safety Topics, Washington Department of Labor & Industries
- Hydration - Urine Color Chart, U.S. Army Public Health Command
- Heat Stress, Farmworker Health and Safety, trainer guide and work book, OSHA FOP 2010
- Heat-related Illness in WA State Agriculture and Forestry Sectors, Research finding, SHARP 2014
- Preventing Heat-related Illness or Death of Outdoor Workers, Workplace Solutions, NIOSH 2013
- Heat Stress, Health Topic Alert, National Center for Farmworker Health 2013
- Beat Heat Before Illnesses Hit, Western Farmer Stockman June 2007
- Hot Tips for Heat Stress, Good Fruit Grower July 2007
- Recognizing and Preventing Heat Stress, Good Fruit Grower June 2006
- Heat-related Deaths Among Crop Workers - United States, 1992-2006, is a crop worker hazards collage published by the CDC in June 2008. It provides a case study of a crop worker's heat-related death and summarizes heat-related fatalities among crop production workers during a 15-year period.
- Workplaces Safety & Health Topics, Heat Stress, NIOSH/CDC
- Heat Stress, Oregon Occupational Safety and Health Association
- Campaign to Prevent Heat Illness, Occupational Safety and Health Association
- Heat-related Illness in Washington State, State Fund Workers’ - Compensation Claims, 1995 – 2004
- Heat Illness, Medline Plus
- Heat Illness Prevention, Division of Agriculture and Natural Resources, University of California
- Criteria for a Recommend Standard: Occupational Exposure to Heat and Hot Environments, National Institute of Occupational Safety and Health,/CDC, 2016