Interpretation Response #21-0060
Below is the interpretation response detail and a list of regulations sections applicable to this response.
Interpretation Response Details
September 28, 2021
Trooper Scott Maguire
Massachusetts State Police
906 Elm Street
Concord, MA 01742
Reference No. 21-0060
Dear Mr. Maguire:
This letter is in response to your May 25, 2021, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to portable tanks and cargo tanks. We have paraphrased and answered your questions as follows:
Q1. You ask whether it is permissible to weld a specification Department of Transportation (DOT) 51 portable tank to a chassis and convert it to a cargo tank motor vehicle (CTMV) for the transportation of liquefied petroleum gas (LPG).
A1. The answer is no. The definition of a "cargo tank" as specified in § 171.8 of the HMR does not authorize a bulk packaging that is fabricated to the specification of a portable tank. Additionally, the HMR defines a CTMV as a "motor vehicle with one or more cargo tanks permanently attached to or forming an integral part of the motor vehicle." Therefore, a DOT 51 portable tank which has been permanently attached to a motor vehicle would not constitute a CTMV as the tank is not an integral part of the motor vehicle.
Q2. You ask whether a specification DOT 51 portable tank retains its specification after being permanently attached to a vehicle.
A2. The answer is no. The portable tank as described in your inquiry was originally fabricated as a specification DOT 51 portable tank. However, once the specification DOT 51 portable tank was permanently attached to the motor vehicle, it no longer meets the definition of a "portable tank" as defined in § 171.8. Therefore, the specification DOT 51 portable tank loses its specification because it can no longer be defined as a "portable tank." See Answer A1.
Q3. You ask whether § 173.32(a)(3) applies to both specification and non-specification portable tanks.
A3. The answer is yes. The use of portable tank requirements in § 173.32(a)(3) can apply to both specification and non-specification portable tanks.
I hope this information is helpful. Please contact us if we can be of further assistance.
T. Glenn Foster
Chief, Regulatory Review and Reinvention Branch
Standards and Rulemaking Division
|§ 173.32||Requirements for the use of portable tanks|