Large items can be tested by using walk-in chambers.
An Environmental Chamber is an enclosed space where environmental conditions such as temperature and humidity can be controlled. 
Mainly used for manufacturing and maintaining constant temperature and humidity space, the constant temperature and humidity device refrigeration, heating, dehumidification, humidification, replenishment of humidified water, and other fully automatic control, the equipment can be attached (optional) air exchange function, can be in the internal bad volatile gas when allowing personnel to operate in the internal long-term.