Japan's 'Human Refrigerator': Vending Machine Maker Develops Cooling Booth To Beat Extreme Heat

As Japan grapples with increasingly severe summer heat, a vending machine manufacturer has developed an unusual solution: a human-sized stainless-steel refrigerator designed to cool one person at a time and help prevent heatstroke.

Japanese manufacturer SDRS's Do Hiemon Box functions as a personal cooling booth, blowing air as cold as 5°C through vents at the top and rear. The product is being marketed as a quick way for people working or spending time outdoors to escape extreme temperatures.

How Does The 'Human Refrigerator' Work?

The Do Hiemon Box is an insulated stainless-steel enclosure measuring 1.75 metres (5.7 feet) in height and designed to accommodate a single person on a narrow seat.

Users can adjust the temperature and airflow through three settings, while cool air is circulated through vents positioned at the top and back of the booth.

The unit is mounted on casters and runs from a regular electrical outlet, allowing it to be moved between locations. Its developers envisage it being used at construction sites, factories and outdoor events where workers and visitors may need temporary relief from extreme heat.

Trusco Nakayama, which sells the product, claims that the booth can help cool the entire body in about 20 minutes while consuming roughly half the energy of an average portable air conditioner.

The company describes the concept as a "human refrigerator" and says it offers full-body cooling compared with wearable solutions such as fan-equipped jackets, which are commonly used by outdoor workers in Japan.

Why Is Japan Turning To Extreme Cooling Solutions?

The development comes as Japan experiences increasingly intense summer temperatures and a growing number of heat-related illnesses.

Japan recorded a particularly severe heatwave last year, while meteorologists have adopted the term "kokushobi", meaning "cruel heat day", for days when temperatures reach 40°C or higher.

Recently, Japan experienced an unprecedented five consecutive days of kokushobi conditions. In Tokyo alone, 453 people were reportedly hospitalised for heat-related illness in a single day — the highest figure recorded since monitoring began more than a decade ago. At least 14 people died across the country during the heatwave.

The extreme conditions have increased demand for ways to protect people who cannot simply remain indoors in air-conditioned spaces.

The Do Hiemon Box is particularly aimed at workers and others who spend long periods outside, offering a dedicated space where they can temporarily escape the heat.

Can 'Human Refrigerators' Solve The Heat Problem?

The cooling booth reflects a broader challenge facing countries experiencing more frequent and intense heatwaves: many solutions designed to protect people from heat also consume significant amounts of energy.

Air conditioning remains one of the most common ways of coping with extreme temperatures, but it contributes to the problem in several ways. Air-conditioning systems release waste heat into their surroundings and consume electricity, while refrigerants can contribute to warming when they leak.

The Do Hiemon Box is being promoted partly on its lower energy consumption compared with portable air conditioners. But it is ultimately a short-term adaptation to increasingly dangerous heat rather than a solution to the underlying climate crisis.

For Japan's outdoor workers and event-goers, however, the "human refrigerator" could offer something increasingly valuable during the country's hottest days: a small, mobile refuge from extreme heat.