49 CFR § 179.220-25 - Stamping.

(a) To certify that the tank complies with all specification requirements, each outer shell must be plainly and permanently stamped in letters and figures at least 3/8-inch high into the metal near the center of both outside heads as follows:

	Examples of required stamping
Specifications	DOT-115A60W6.
Inner container:
Material	ASTM A240–316L.
Shell thickness	Shell 0.167 in.
Head thickness	Head 0.150 in.
Tank builders initials	ABC.
Date of original test	00–0000.
Outer shell:
Material	ASTM A285–C.
Tank builders initials	WYZ.
Car assembler (if other than inner container or outer shell builders)	DEF.

(b) After July 25, 2012, newly constructed DOT tank cars must have their DOT specification and other required information stamped plainly and permanently on stainless steel identification plates in conformance with the applicable requirements prescribed in § 179.24(a). Tank cars built before July 25, 2012, may have the identification plates instead of or in addition to the head stamping.

[Amdt. 179–9, 36 FR 21343, Nov. 6, 1971, as amended at 77 FR 37986, June 25, 2012]