Previous outdoor workplace guidelines, for jobs such as construction workers, said a heat index in the 80s was "low risk."
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But a new review of workplace heat illness by the CDC showed six cases of heat related deaths when the heat index was between 85 and 91 degrees.
CDC advice: Employers should exercise caution if the Heat Index is 85 degrees or higher. That temperature should be even lower if you work in heavy clothing or are highly active.
And as we said at the beginning: More water, more shade, more breaks. Advice we can all use this week of record-breaking heat.