A large-scale room calorimeter has been developed for testing surface lining materials as well as furniture and other fittings. Heat release rates in the fire room have been measured in various ways. The technique based on oxygen consumption was deemed to be the most suitable for a standard test. A hood has therefore been built to collect all the fire gases leaving the room; thus, the rates of production of smoke and various chemical compounds can readily be measured and give a good basis for estimating the fire hazard of a specimen. As it is extremely difficult to scale fire tests there is an urgent need for evaluating laboratory scale tests. This accurately defined, full-size method could serve as an invaluable tool for this purpose. Tests of several wall lining materials and pieces of furniture are reported in the paper.