Electric heaters are safe to use when installed correctly.
The Safety Technology Authority (Turvatekniikan keskus) monitors the electrical safety standards of heaters and gives manufacturers and heaters a certificate of safety. In Finland approved heaters are marked FI. Heaters may carry certificate labels from other countries. Heaters are connected to the mains supply in such a way that their touching metallic parts are earthed. Live components are prevented from coming into contact with one another as part of the design.