Pennsylvania Statutes Title 53 P.S. Municipal and Quasi-Municipal Corporations § 24962. Heating apparatus

Every steam boiler which may be required for heating or other purposes shall be located outside of the building and the space allotted to the same shall be enclosed by walls of masonry on all sides, and the ceiling of such space shall be constructed of fireproof material.  All doorways in said walls shall have iron doors.  No floor register for heating shall be permitted.  No coil or radiator shall be placed in any aisle or passageway used as an exit where it forms an obstruction, but all said coils and radiators shall be placed in recesses formed in the wall or partition to receive the same.  All supply, return or exhaust pipes shall be properly encased and protected where passing through floors or near woodwork.