Location of Name Plate and Requalification Markings on DOT 51 Portable Tank
Pipeline and Hazardous Materials Safety Administration · Jul 12, 1999 · Reference No. 99-0168
Reggie’s quick take
Someone asked whether the name plate and requalification markings on a DOT 51 portable tank meet the rules when the tank sits upright inside a square metal frame and its plates can be seen only after lifting a hinged top cover. PHMSA said no. The name plate must be close to the ASME Full stamp under § 178.245-6, and the retest date must be on or near the metal certification plate under § 173.32(e)(3). Under § 178.3(a)(1), markings must be in an unobstructed area, and markings hidden by a cover do not qualify.
Written by AI (Claude) on Oct 22, 2026. Robots make mistakes and leave things out, so the letter below is what counts. Not legal advice.
This is in response to your June 15, 1999 request concerning the location of the name plate and requalification markings on a DOT 51 portable tank.
The portable tank in question is in an upright position on its ends and is enclosed by a square metal configuration. Access to the tank valves, the ASME and DOT specification plates, and the requalification markings is achieved by lifting a hinged top cover. You submitted drawings of a portable tank for our review and asked if the location meets the requirements of the regulations.
The answer is no. Section 178.245-6 requires the name plate with the required markings to be in close proximity to the ASME Full stamp certification. Paragraph UG-116(j) of the ASME Code states that the markings must be in a conspicuous place on the vessel, preferably near a manhole or handhole. With regard to the periodic retest marking, § 173.32(e)(3) of 49 CFR requires the date of the most recent periodic retest to be marked on the tank, on or near the metal certification plate, in accordance with § 178.3. Section 178.3(a)(1) states that the specification marking must be in an unobstructed area. Markings that are obscured from view by a cover do not satisfy the requirement for an unobstructed area.
A letter of interpretation applies the regulations to the facts the requester described. It isn’t a regulation and isn’t legal advice. The agency’s copy.