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OSHA-NIOSH Heat Safety Tool App

Key considerations for using the app
  • Heat index (HI) values were created for shady, light wind conditions, so exposure to full sunshine can increase heat index values by up to 15°F.
  • The simplicity of the HI makes it a good option for many outdoor work environments (if no additional radiant heat sources are present, such as, fires or hot machinery). However, if you have the ability, NIOSH recommends using wet bulb globe temperature (WBGT)-based Recommended Exposure Limits (RELs) and Recommended Alert Limits (RALs) in hot environments.
  • Use of the HI or WBGT is important, but other factors such as strenuous physical activity also cause heat stress among workers. Employers should have a robust heat stress prevention program that ensures workers are protected.
  • NIOSH and the Occupational Safety and Health Administration (OSHA) are considering new scientific data related to the HI levels, and considering how to best incorporate the evolving science. It is important to regularly download updates to ensure you are using the latest version of the app.
IPhone front view showing the OSHA NIOSH Heat Safety tool. Screen reads feels like 112 degrees with orange button

The OSHA-NIOSH Heat Safety Tool is a useful resource for planning outdoor work activities based on how hot it feels throughout the day. It has a real-time heat index and hourly forecasts specific to your location. It also provides occupational safety and health recommendations from OSHA and NIOSH.

The OSHA-NIOSH Heat Safety Tool features:

  • A visual indicator of the current heat index and associated risk levels specific to your current geographical location
  • Precautionary recommendations specific to heat index-associated risk levels
  • An interactive, hourly forecast of heat index values, risk levels, and recommendations for planning outdoor work activities
  • Location, temperature, and humidity controls, which you can edit to calculate for different conditions
  • Signs and symptoms and first aid for heat-related illnesses
Get the OSHA NIOSH Heat Index App on the Apple App Store

Get the OSHA NIOSH Heat Index App on the Google Play Store