A Useful Tool for Heat Illness Prevention

We are now well into the summer season and employers are busy taking the necessary steps to protect workers from the risks of heat illness during work in high heat conditions.  You may not be aware that Federal OSHA has developed and has recently updated a very useful tool that provides vital safety information regarding the levels of heat risk at actual temperature conditions and appropriate protective measures for each risk level.  The “OSHA Heat Safety Tool” is an application for both the iPhone and Android phones that can be downloaded from the OSHA web site (https://www.osha.gov/SLTC/heatillness/heat_index/heat_app.html).

The OSHA heat tool is based on the heat index developed by the U.S. National Oceanographic and Atmospheric Administration (NOAA).  It combines both air temperature and relative humidity into a single value that indicates the apparent temperature in degrees Fahrenheit, or how hot the weather will feel.  The higher the heat index, the hotter the weather will feel, and the greater the risk that outdoor workers will experience heat-related illness.  NOAA issues heat advisories as the heat index rises.  The App (available in a Spanish version) 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,” the user can get reminders about the protective measures that should be taken at that risk level to protect workers from heat-related illness.

Using the OSHA phone app is quite simple.  The user can enter temperature and humidity values on the home screen and then click “calculate” to display the resulting heat index value and the corresponding risk level.  The four levels are shown below.

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If the temperature and humidity values are unknown, the user can press either the “Get Current” or “Get Today Max” button at the top of the screen to get the corresponding data from the NOAA website.  Once the risk level is determined, the user can press the “Precautions” button to receive additional information regarding the recommended precautions that should be taken to prevent heat illness.  These include 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.  One note of caution: the NOAA heat index values were developed for shady, light wind conditions and exposure to full sunshine can increase the heat index values by up to 15 ºF.  To account for the solar load, as well as strenuous work and the use of heavy or specialized protective clothing, OSHA recommends additional precautions.  Thus, the OSHA Heat Tool provides only an approximate indicator of the true heat index and the risk level to workers.  The user must always take the impacts of work levels, clothing and environmental conditions into account when using what appears to be a simple, straight-forward tool.

Nonetheless, the OSHA Heat Safety Tool can be a useful aid in helping to assess workplace conditions on a daily basis (and as conditions change during the day) and determining what steps should be taken to protect employees.  Employers should continue to implement their heat illness prevention plans, as required by the Cal/OSHA Heat Illness Prevention standard, and ensure that workers at jobsites are provided with sufficient quantities of cool drinking water, access to shade, and are encouraged to take preventative cool-down rest breaks to protect themselves from overheating.