The human body can tolerate a range of temperatures, but there are critical limits beyond which heat becomes life-threatening. Here are the key points about human heat tolerance:
The normal core body temperature is around 37°C. When the core body temperature rises to 40°C or higher, it becomes dangerous and can lead to heat-related illnesses such as heat exhaustion or heat stroke.
The heat index combines air temperature and humidity to reflect how hot it feels. When the heat index reaches 39°C to 42°C, it poses a high risk of heat-related illness. A heat index of 54°C or higher is considered extremely dangerous and can cause heat stroke within minutes.
In extremely high temperatures, particularly those above 35°C with high humidity, the body struggles to cool itself through sweating. Prolonged exposure to temperatures around 54°C or higher without adequate cooling or hydration can be fatal within a short time.
The wet-bulb temperature is a measure that accounts for temperature, humidity, and wind speed. A wet-bulb temperature of 35°C is considered the limit of human survivability, beyond which the body can no longer effectively cool itself, leading to hyperthermia and potentially death within hours.