(a) Where Class II systems are used, heating shall be by steam or hot water only. Steam and hot water pipes and radiators for heating and drying purposes shall be at least one inch from all woodwork and shall be protected by substantial metal screens arranged so as to prevent combustible goods or materials from coming in contact with pipes and radiators.
(b) Boilers shall be located in a detached building or in a boiler room cut off from the dry cleaning room. For Class II systems this cut-off shall be by a fire wall without openings. Openings into such boiler rooms shall be at least 10 feet from any exterior openings into the cleaning room. For Class III systems this cut-off shall be by a fire partition without openings, having a fire-resistance rating of not less than two hours.