All low pressure boilers that are used for building or space heat shall be built in accordance with ASME Section IV and shall bear the ASME Certification Mark and "H" designator. The use of hot water heaters, those with the ASME "HLW" designator or those listed as meeting the requirements of ANSI Z 21.10.13 Gas-Fired Water Heaters, shall not be used for building or space heat. Dual purpose units shall be built in accordance with ASME Section IV and shall bear the ASME Certification Mark and "H" designator.
229 Neb. Admin. Code, ch. 24, § 009