Flame-protected enclosure (or machine)
Alternative term: Flameproof enclosure (or machine)
An enclosure (or machine) designed to withstand an internal explosion of a given flammable gas and to prevent an internal flame from passing outside to ignite a given flammable gas in the surrounding atmosphere.
Please note that this is the term as it stands in the original IALA Dictionary edition (1970-1989)
International Association of Marine Aids to Navigation and Lighthouse Authorities - AISM