For the use of unflued appliances in a confined space. These are general requirements - those for specific appliances may vary from these - see appliance instructions.
1. The volume of the room space in which an appliance is used must be at least 10m3 for each 1kW of continuous heat input with a minimum room size of 15m3. This is in addition to the volume required for other appliances.
2. Permanent ventilation must be provided by at least 25cm2 of free ventilation area for each kW of continuous heat input. This is in addition to that required for other appliances and the occupants, and there must be a minimum of 50cm2 of free ventilation area. The ventilation area must be divided between high and low level, and the ventilators must be constructed so that they cannot be closed. If the space is to be used for sleeping, the appliances must be turned off before retiring.