Rather than being waterproof, bathroom heaters are often wall mounted for safety, according to Air and Water. In addition, portable heaters have ALCI plugs that interrupt current if the appliance meets water, states Home Depot and Bed, Bath and Beyond.
Electric bathroom heaters are often placed on or into the walls, Air and Water says. This significantly reduces the risk of water exposure. Infrared heaters are also readily mounted to walls. Because they only heat whatever is close, both types of heaters are typically energy-efficient.
An ALCI -- appliance leakage circuit interrupter -- plug shuts power off to an appliance when it is exposed to water, reports the Electric League of Missouri and Kansas. However, it is still not safe to immerse a ALCI-plug device in water and then retrieve it. These appliances should never be left unattended, TRC instructs.
Even if space heaters are identified as bathroom-safe, that does not necessarily mean that they prevent electric shock when the room is damp, advises Consumer Reports. Even with safety plugs, some manufacturers do not recommend using their devices near water. In general, space heaters are designed to shut off if they tip or become too hot. However, they cause about one-third of residential heating fires.