Gives the requirements and test procedures for the safety, construction, classification and marking of non-domestic gas fired overhead radiant tube heaters that include a single burner control system. Applies to type A[2], A[3], B[12], B[13], B[22], B[23], C[12], C[13], C[32] and C[33] appliances, intended for use in other than domestic dwellings, in which the supply of combustion air and/or the evacuation of the products of combustion is achieved by mechanical means located upstream of the draught diverter, if provided.