What does 49 CFR 180.212 (Repair of seamless DOT 3-series specification cylinders and seamless UN pressure receptacles) require?

Short answer

49 CFR 180.212 requires that repair of seamless DOT 3-series specification cylinders and seamless UN pressure receptacles be performed by an approved facility, with specific conditions for grinding, ultrasonic examination, and requalification.

The rule says

"No person may repair a DOT 3-series cylinder or a seamless UN pressure receptacle unless (i) The repair facility holds an approval issued under the provisions in 107.805 of this chapter; and (ii) Except as provided in paragraph (b) of this section, the repair and the inspection is performed under the provisions of an approval issued under subpart H of part 107 of this chapter or by a facility registered by Transport Canada in accordance with the Transport Canada TDG Regulations (IBR; see 171.7 of this subchapter) and conform to the applicable cylinder specification or ISO standard contained in part 178 of this subchapter." (49 CFR 180.212(a)(1))

"Grinding must not be used to remove arc burns from a cylinder, as such a cylinder must be condemned" (49 CFR 180.212(a)(3))

"Ultrasonic examination must be conducted to ensure that the wall thickness is not less than the minimum design requirement." (49 CFR 180.212(a)(3)(i))

In plain English

This rule is about ensuring that repairs to certain types of cylinders are done safely and correctly. It requires that the repair facility have the necessary approval and follow specific procedures, including ultrasonic examination after grinding, to ensure the cylinder's integrity. The rule also prohibits grinding to remove arc burns, as this can weaken the cylinder. In practice, this means that facilities must have a robust quality control process in place to ensure that repairs are done correctly and that cylinders are safe for use.

What to do

• Ensure your facility has the necessary approval under 107.805 to perform repairs on seamless DOT 3-series specification cylinders and seamless UN pressure receptacles.
• Develop and follow a procedure for grinding and ultrasonic examination that meets the requirements of 49 CFR 180.212.
• Train personnel on the correct procedures for repairing and inspecting cylinders.
• Maintain records of repairs and inspections as required by 49 CFR 180.215.