The theme of this year’s Heat Action Day (2 June 2026) confronts the threat of extreme heat on people working, living or studying within doors.
At a school on the Unguja Island, part of the Tanzanian archipelago known as Zanzibar, volunteers from the Tanzania Red Cross Society explain to a classroom full of students how to protect themselves from the dangers of extreme heat.
The volunteers’ efforts were part of a larger heatwave awareness campaign in early 2026, led by the Tanzanian Red Cross, that has reached more than 4,000 people in schools, madrasas, markets, and communities around the island.
This is just one of many ways Red Cross and Red Crescent National Societies around the world regularly work to protect people from the dangers of extreme heat – including the very particular dangers of indoor heat.
When thinking about or preparing for heatwaves, people often think of blistering days outside in the hot sun. But people living or working indoors, in uncooled or poorly ventilated spaces, can sometimes be at even greater risk of heat stroke, dehydration and other heat-related risks.
Those most susceptible to rising body temperatures — children and the elderly — are particularly vulnerable and, often, they must spend long periods of the day inside.
These are some of the reasons Heat Action Day 2026 focuses on ‘indoor heat’ — putting the spotlight on the health risks people face inside their homes, schools, workplaces, care facilities, transport hubs, prisons and even public vechiles such as busses and taxis. (Learn more about how to #BeatTheHeat and about how to take part in Heat Action Day 2026.)
This threat is nothing new to Red Cross and Red Crescent volunteers who often go door-to-door during heatwaves, visiting people who live in densely populated urban neighborhoods, work in poorly insulated industrial areas, or live in camps for people displaced by emergencies.
Very often, such facilities or temporary shelters lack insulation or access to energy or water sources that can help keep people cool. Building materials, design characteristics, and urban heat island all play a role in determining indoor temperatures.
