Both types of electric water heaters, tankless and storage, are safe for the shower when properly installed and cared for. Tankless electric water heaters attach directly to the showerhead.
Because of their proximity to the water supply line, tankless electric water heaters must be powered from a dedicated circuit breaker or a GFCI receptacle, a particular type of safety outlet. Poorly insulated or installed electrical wiring for this type of water heater may result in electric shock. The outlet should also be located a safe distance from the shower itself. Storage electric water heaters minimize certain dangers, such as combustion and carbon dioxide poisoning, but still require regular inspection and maintenance to ensure key mechanisms like thermostats and pressure valves are operating properly.