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(a) Hot work requiring testing by a Marine Chemist or Coast Guard authorized person.
(1) The employer shall ensure that hot work is not performed in or on any of the following confined and enclosed spaces and other dangerous atmospheres, boundaries of spaces or pipelines until the work area has been tested and certified by a Marine Chemist or a U.S. Coast Guard authorized person as "Safe for Hot Work":
(i) Within, on, or immediately adjacent to spaces that contain or have contained combustible or flammable liquids or gases.
(ii) Within, on, or immediately adjacent to fuel tanks that contain or have last contained fuel; and
(iii) On pipelines, heating coils, pump fittings or other accessories connected to spaces that contain or have last contained fuel.
(iv) Exception: On dry cargo, miscellaneous and passenger vessels and in the landside operations within spaces which meet the standards for oxygen, flammability and toxicity in §1915.12, but are adjacent to spaces containing flammable gases or liquids, with a flash point below 150°F (65.6°C) when the distance between such spaces and the work is 25 feet (7.62m) or greater.
Note to Paragraph (a)(1)(iv):
For flammable liquids with flash points above 150°F (65.6°C), see paragraph (b) of this section.
(2) The certificate issued by the Marine Chemist or Coast Guard authorized person shall be posted in the immediate vicinity of the affected operations while they are in progress and kept on file for a period of at least three months from the date of the completion of the operation for which the certificate was generated.
(b) Hot work requiring testing by a competent person.
(b)(1)Hot work is not permitted in or on the following spaces or adjacent spaces or other dangerous atmospheres until they have been tested by a competent person and determined to contain no concentrations of flammable vapors equal to or greater than 10 percent of the lower explosive limit:
(i) Dry cargo holds,
(ii) The bilges,
(iii) The engine room and boiler spaces for which a Marine Chemist or a Coast Guard authorized person certificate is not required under paragraph (a)(1)(i) of this section, and
(iv) Vessels and vessel sections for which a Marine Chemist or Coast Guard authorized person certificate is not required under paragraph (a)(1)(iv) of this section, and
(v) Land-side confined and enclosed spaces or other dangerous atmospheres not covered by paragraph (a)(1) of this section.
(2) If the concentration of flammable vapors or gases is equal to or greater than 10 percent of the lower explosive limit in the space or an adjacent space where the hot work is to be done, then the space shall be labeled "Not Safe for Hot Work" and ventilation shall be provided at volumes and flow rates sufficient to ensure that the concentration of flammable vapors or gases is below 10 percent by volume of the lower explosive limit. The warning label may be removed when the concentration of flammable vapors and gases are below 10 percent lower explosive limit.
Note to §1915.14: See Appendix A of this Subpart for additional information relevant to performing hot work safely.