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While an explosion-proof refrigerator might sound like an ideal kitchen appliance for frazzled parents, it is not something most people would want in their homes. That is, unless you plan on storing flammable material and containers of explosive gases next to the pot roast in your freezer. If you are a worker in a professional laboratory, however, an explosion-proof refrigerator could literally save your life.
This type of refrigerator performs essentially the same basic functions as its plug-in, frost-free kitchen counterpart. There is usually a refrigerated compartment which keeps objects cold but not freezing. An explosion-proof refrigerator may also have an insulated freezer compartment for keeping frozen items frozen.
The key phrase to keep in mind is explosion-proof. Laboratory workers routinely work with flammable or explosive materials. Some of these materials must be kept cool or even frozen. This is why they must be stored in an explosion-proof refrigerator away from other flammable materials or points of ignition. Meanwhile, the atmosphere around the refrigerator may become volatile or flammable from room-temperature experiments elsewhere. Great care must be taken to keep the two environments separate and safe.
Because a typical refrigerator contains a number of potential electrical ignition points, an explosion-proof refrigerator must be modified to make it safer. Shields are placed around light sources to prevent accidental sparks, and the wiring to the compressor and motor are hidden inside the insulated walls or harnessed outside the unit entirely. This type of refrigerator is not plugged into a wall socket, but actually hard-wired directly into the building's electrical system. There can be no chance of an electrical short or overheated coil igniting a flammable or explosive substance stored inside the refrigerator.
A truly explosion-proof refrigerator can be very expensive to install and maintain, so other less-expensive safety measures are often employed in areas where the atmosphere is rarely volatile or explosive. Such a refrigerator is only essential whenever the environment outside the unit is just as hazardous as the environment inside. The safe storage of flammable or explosive materials should always be a consideration for laboratories, but an explosion-proof refrigerator may not be strictly necessary for many routine processes not involving the production of flammable gases or volatile materials.
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