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Heat Stress Guidelines for Work Limits

Discontinue Work If Any of the Following Occur

  • Sustained Heart Rate minus the individual's age is above 180 beats per minute. (Heart Rate - Age > 180)
  • Recovery Heart Rate at one minute after a peak work effort is great than 100 beats per minute.
  • Body Core Temperature is greater than 101.3 F (38.5 C) for medically selected and acclimated workers
  • Body Core Temperature is greater than 100.4 F (38.0 C) in unselected, un-acclimatized workers.
  • Sudden and severe fatigue, nausea, dizziness, or lightheadedness.
  • Workers appear disoriented or confused, or suffer inexplicable irritability, malaise, or flu-like symptoms.
  • Sweating stops and skin becomes hot and dry. Seek immediate emergency care with hospitalization. Call ext. 2222 on site.
  • Profuse sweating is sustained over a couple of hours.
  • Weight loss over a shift is greater than 1.5% ob body weight.
  • 24 hour urinary sodium excretion is less than 50 nmoles.