This standard establishes the requirements applicable to rooms or enclosures that house, well generators for the production of heat or cold by heat transfer fluid, excluding air and including water vapour with a maximum working pressure not exceeding 0,5 bar , whose combined rated output exceeding 70 kW, or cogeneration equipment with nominal heat input exceeding 70 kW, using gaseous fuels of the families defined in the standard UNE-EN 437. This standard also applies to stand-alone equipment, generating either heat or cold, or for cogeneration, outdoor installed.