46 CFR 56.60-3: -3 Ferrous materials.

(a) Ferrous pipe used for saltwater service must be protected against corrosion by hotdip galvanizing or by the use of extra heavy schedule material.

(b) (Reproduces 124.2.C.) Carbon or alloy steel having carbon content of more than 0.35 percent must not be used in welded construction, nor be shaped by oxygen-cutting process or other thermal-cutting process.