Tool: Heat Index – Summary of Risk Levels and Associated Protective Measures

• Provide drinking water
• Ensure that adequate medical services are available
• Plan ahead for times when the heat index is higher, including worker heat safety training
• Encourage workers to wear sunscreen
• Acclimatize workers

If workers must wear heavy protective clothing, perform a strenuous activity or work in the direct sun, additional precautions are recommended to protect workers from heat-related illness. ^*

In addition to the steps listed above:

• Remind workers to drink water often (about 4 cups/hour)^**
• Review heat-related illness topics with workers: how to recognize heat-related illness, how to prevent it, and what to do if someone gets sick
• Schedule frequent breaks in a cool, shaded area
• Acclimatize workers
• Set up buddy system/instruct supervisors to watch workers for signs of heat-related illness

If workers must wear heavy protective clothing, perform a strenuous activity or work in the direct sun, additional precautions are recommended to protect workers from heat-related illness.^*

• Schedule activities at a time when the heat index is lower
• Develop work/rest schedules
• Monitor workers closely

In addition to the steps listed above:

• Alert workers of high-risk conditions
• Actively encourage workers to drink plenty of water (about 4 cups/hour) ^**
• Limit physical exertion (e.g. use mechanical lifts)
• Have a knowledgeable person at the worksite who is well-informed about heat-related illness and able to determine appropriate work/rest schedules
• Establish and enforce work/rest schedules
• Adjust work activities (e.g., reschedule work, pace/rotate jobs)
• Use cooling techniques
• Watch/communicate with workers at all times

When possible, reschedule activities to a time when the heat index is lower

Reschedule non-essential activity for days with a reduced heat index or to a time when the heat index is lower

Move essential work tasks to the coolest part of the work shift; consider earlier start times, split shifts, or evening and night shifts.

Strenuous work tasks and those requiring the use of heavy or non-breathable clothing or impermeable chemical protective clothing should not be conducted when the heat index is at or above 115°F.

If essential work must be done, in addition to the steps listed above:

• Alert workers of extreme heat hazards
• Establish water drinking schedule (about 4 cups/hour) ^**
• Develop and enforce protective work/rest schedules
• Conduct physiological monitoring (e.g., pulse, temperature, etc.)
• Stop work if essential control methods are inadequate or unavailable.