What temperature will instantly kill people?

There is no specific temperature that will instantly kill a person, as it depends on various factors such as exposure time, humidity, and individual health conditions. However, extreme temperatures above 70°C (158°F) can cause severe burns and potentially lead to death if sustained. In terms of cold, temperatures below -40°C (-40°F) can lead to hypothermia and frostbite, which can also be fatal if exposure is prolonged. Ultimately, survival depends on multiple variables rather than a single temperature threshold.