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Stopping for Water Keeps You Going

When working in extreme heat and humidity, a person can lose three to four liters of water per hour, or as much as ten liters per day. The effects of dehydration begin when a body loses just 1% of its weight in water and become life-threatening at 10% loss.

Follow the basic guidelines of "Water, Rest, Shade" when outdoors for extended time periods.

Stay Hydrated

  1. Drink 16-20 oz. of water 2-4 hours prior to working in the heat.
  2. Plan to bring 1.0 to 1.5 liters of water for every hour to be spent working in the heat.
  3. Drink 8-12 oz. of water every 15 minutes when working in the heat.
  4. Use work-rest cycles.
  5. Use the NIOSH heat safety tool to determine your risk.
  6. Use the hydration self-assessment tool.
  7. If work in the heat exceeds 60 minutes, consume a 20 oz. sports drinks (e.g., Gatorade, Powerade) in addition to your water consumption to replenish lost electrolytes.

Heat Illness Can Be Deadly

Remember to: 

  • Drink water often, even if you aren’t thirsty
  • Rest in the shade or A/C to cool down
  • Report heat symptoms early
  • Know what to do in an emergency


Last Modified: Aug 22, 2022
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