46 C.F.R. § 115.710
(a) An inspection for flammable or combustible gases must be conducted by a certified marine chemist or other person authorized by the cognizant OCMI in accordance with the provisions of National Fire Protection Association (NFPA) 306, “Control of Gas Hazards on Vessels,” before alterations, repairs, or other operations involving riveting, welding, burning, or other fire producing actions may be made aboard a vessel:
(b) An inspection required by paragraph (a) of this section must be conducted as required by this paragraph.