Imagine you are working in a Vietnamese shoe factory without air conditioning. During the hot season, as temperatures soar towards 40°C inside the stifling building, your production targets remain fixed. To maintain your output you are allowed to take a little longer on your breaks to cool down. Still, the sweltering heat means that you just can’t work as efficiently, so in order to complete your work you start an hour earlier and finish later.
Heat stress is a fact of life for the majority of the world. Indeed, cultures have been shaped by efforts to avoid heat. A well-known example is the Mediterranean siesta, which signals a work break during the hottest part of the day. Similar adaptations to heat have occurred in the tropics where work begins earlier, ends later and is carried out more slowly.
Despite these precautions, severe heat stress regularly kills. The dangers of sequential days and nights with elevated temperatures, referred to as heat waves, are well-known by communities and authorities in Australia. For example, in southern Australia during the record-breaking heat wave that led to the devastating “Black Saturday” bushfires of 2009, more lives were claimed by heat stress than by the fires themselves.
A high profile heat wave in western Europe killed more than 35,000 people during 2 weeks in the summer of 2003.
Most of the deaths...
