Heat stress

Heat stress happens when workers do physical work in hot conditions. It can cause heat illness, and in severe cases heat stroke, which can kill. Heavy work raises the risk. NIOSH examples of heavy work include climbing, carrying equipment or supplies weighing 40 pounds or more, and using hand tools for long periods. Even moderate work at 108 °F carries a high risk of heat injury and calls for extreme caution. A work/rest schedule is the main control. For example, NIOSH says heavy work at 104 °F should follow 20 minutes of work with 40 minutes of rest. Drink water often and have coworkers watch each other for signs of heat illness. In the NIOSH case study, crews who did this got affected workers to medical care early, and those workers recovered. In extreme heat, a work/rest schedule alone may not remove the risk. Use all of these controls together.

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• sentence 1: support check: partial - Heat illness and life-threatening heat stroke are stated, and physical work in heat is implied by the examples, but no passage defines heat stress as arising from physical work in hot conditions.
• sentence 2: support check: partial - The heavy work examples match, but the passages don't explicitly say heavy work raises the risk, though the work/rest example implies heavier work needs more rest.
• sentence 4: support check: partial - The 20/40 example for heavy work at 104 °F is stated, but the passages don't call the work/rest schedule the main control, and attributing it to NIOSH is only loosely supported.
• sentence 5: support check: partial - Hydration and team monitoring helped, and the workers recovered, but the passages don't say affected workers got care 'early'; they say only that coworkers noticed signs and workers were sent to the medical station.
• sentence 1: review: partial - Heat illness and life-threatening heat stroke are stated, but no passage defines heat stress as arising from physical work in hot conditions.
• sentence 4: review: partial - The example of 20 minutes of work and 40 minutes of rest for heavy work at 104 °F is stated, but no passage calls work/rest schedules the main control. -->