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Safety Spotlight - Indoor Heat Illness Prevention

By Risk Management

June 04, 2019 - 08:44 PM

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As warmer weather approaches, the topic of heat illness prevention is usually discussed in relation to outdoor activities. It is equally important to evaluate heat illness prevention pertaining to indoor activities. The same safety measures of monitoring, training, and allowing employees to acclimatize to the higher temperatures are important for employees working outdoors or indoors. The following are items to consider when protecting employees from indoor heat illness:

Who is Affected:

  • Employees working indoors in areas where the temperature equals or exceeds 82 degrees Fahrenheit.

Heat Index:

  • The “heat index” is a single value that takes into account both temperature and relative humidity.
  • For employees working in hot environments, both the temperature and relative humidity affect the risk of heat illness.
  • The heat index may be measured using a monitor or by using a chart and rounding up to the nearest temperature and relative-humidity value on the chart. The National Weather Service provides a chart and more information:

Assessment and Control Measures:

  • Initial temperature and heat index measurements must be taken if it is reasonable to suspect indoor temperatures exceed 87 degrees Fahrenheit or the heat index exceeds 87 degrees Fahrenheit
  • Engineering controls must be applied to help reduce the temperature and heat index whenever feasible.
  • Administrative controls, such as staggering work schedules to match cooler times or staggering workloads, should be evaluated and implemented.
  • Personal (heat) protective equipment such as cooling vests should be considered.

Additional Considerations:

  • Know where to access fresh, pure, suitably cool water
  • Know the location of cool-down areas.
  • Train, be trained, on emergency response procedures: maintaining communication with all staff, identifying heat illness symptoms, knowing how to contact emergency medical services.
  • Train, be trained, on Heat Illness Prevention and understand your district’s Heat Illness Prevention Plan.


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