Section 56.90-10 - Threaded piping (modifies 135.5)(a) Any compound used in threaded joints must be suitable for the service conditions and must not react unfavorably with either the service fluid or the piping materials.(b) Threaded joints that are to be seal welded must be made up without any thread compound.CGFR 68-82, 33 FR 18843, Dec. 18, 1968, as amended by USCG-2003-16630, 73 FR 65185 , Oct. 31, 2008