Heat Safety: Know the ‘Real Feel’

Jul. 2, 2019

When planning outdoor work during the summer, keep a close eye on the weather—and not just the raw temperature.

Just as important to heat safety is the heat index, which takes both temperature and humidity into account. High humidity makes perspiration less able to evaporate, lessening the body's natural ability to cool itself.

A heat index (which some meteorologists call the “real feel”) below 91 F is considered low risk, requiring sun protection and adequate amounts of water. A heat index of 91-103 F carries a moderate risk, necessitating readily available water and rest breaks in cool, shaded areas. Heat indexes above these levels may require adjusted work activities and strict work/rest schedules to ensure worker safety. 

At all times and in all warm-weather conditions, ensure that adequate medical services are available and respond to symptoms of heat-related illness and medical emergencies without delay. 

Heat Safety Tool App

The National Institute For Occupational Safety and Health (NIOSH) and OSHA publish a heat index app, which monitors local conditions for a quick assessment of the current heat index and recommended precautions. The app is available through the CDC Website.

Heat Related Illness

There are many different types of heat related illness including: heat stress, heat exhaustion, heat cramps, heat syncope (fainting), and heat rash.

Treating milder symptoms (headache, weakness) early by providing rest in a shaded area and cool water to drink can prevent a more serious medical emergency.
Work safer in hot weather by wearing loose-fitting, lightweight clothing, staying hydrated, preferably with water or sports drinks (avoid caffeine), and recognizing the signs of heat related illness. More tips and information can be found on the Princeton EHS Website.