Section 126.160 - Tests and inspections during repairs or alterations, or during riveting, welding, burning, or other hot work(a) NFPA 306 must be used as a guide in conducting the examinations and issuances of certificates required by this section.(b) Until an examination has determined that work can proceed safely, no riveting, welding, burning, or other hot work may commence.(c) Each examination must be conducted as follows:(1) At any port or site inside the United States or its territories and possessions, a marine chemist certified by the NFPA must make the examination. If the services of such a chemist are not reasonably available, the cognizant OCMI, upon the recommendation of the contractor and the owner or operator of the OSV, may authorize another person to make the examination. If this indicates that a repair or alteration, or hot work, can be undertaken safely, the person performing the examination shall issue a certificate, setting forth the spaces covered and any necessary conditions to be met, before the work starts. These conditions must include any requirements necessary to maintain safe conditions in the spaces covered and must include any necessary further examinations and certificates. In particular the conditions must include precautions necessary to eliminate or minimize hazards caused by protective coatings or by cargo residues.(2) At any port or site outside the United States or its territories and possessions, where the services of a certified marine chemist or other person authorized by the cognizant OCMI are not reasonably available, the master, owner, or operator of the vessel shall make the examination and a proper entry in the OSV's logbook.(d) The master shall obtain a copy of each certificate issued by the person making the examination described in paragraph (c)(1) of this section. The master, through and for the persons under his control, shall maintain safe conditions aboard the OSV by full observance of each condition to be met, listed in the certificate issued under paragraph (c)(1) of this section.