Gas-fired central heating boilers. Type B$d1$d1 and B$d1$d1$dB$dS boilers fitted with atmospheric burners of nominal heat input not exceeding 70 kW— 140 стр.
Non-domestic forced convection gas-fired air heaters for space heating not exceeding a net heat input of 300 kW incorporating a fan to assist transportation of combustion air or combustion products— 156 стр.