This European Standard specifies the requirements, the test methods and the marking of domestic flueless space heaters, including diffusive catalytic combustion heaters, having a nominal heat input (Hs), not exceeding 4,2 kW burning 3rd family gases at nominal operating pressures not exceeding 50 mbar, referred to in the text as 'appliances'. This European Standard is applicable to the following types of appliances: a) fixed heaters burning commercial butane and/or commercial propane; b) portable or mobile heaters burning either commercial butane, or, commercial butane and commercial propane including those that incorporate a LPG container installation comp