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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Interpretation Response #19-0024

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name: AMTROL Water Systems

Individual Name: David Beretta

Location State: RI Country: US

View the Interpretation Document

Response text:

August 14, 2019

Mr. David Beretta
Manger, Compliance & Regulatory
AMTROL Water Systems
1400 Division Road
West Warwick, RI 02893

Reference No. 19-0024

Dear Mr. Beretta:

This letter is in response to your February 26, 2019, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the transportation of water pump systems. In your email, you describe water pump systems containing "UN1956, Compressed gas, n.o.s. (air with up to 15% helium), 2.2" shipped at 38 pounds per square inch (psi) of pressure, with each cylinder weighing approximately 112 pounds each. You also reference a previous letter of interpretation (09-0010) which discusses the application of the limited quantity exception in § 173.306(g) to the water pump systems described above. This previous letter of interpretation clarifies a "single-trip shipment" under § 173.306(g) as a one-time movement of the water pump systems from the facility where they are purchased to the installation site. However, you interpret a "single-trip shipment" as the movement from the manufacturing site to the end-user regardless of whether there is storage incidental to movement before delivery to an installation site. You note that there is no alteration of the package or outer packaging during the storage incidental to movement. You ask whether the described shipment would be considered a "single-trip shipment" under § 173.306(g) if there is storage incidental to movement with no alterations to the package or outer packaging prior to delivery at the installation site.

Provided the water pump systems and any packaging/outer packaging are unaltered, the scenario described in your email would qualify as a "single-trip shipment" under § 173.306(g) and the limited quantity exception would apply.

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


Regulation Sections

Section Subject
173.306 Limited quantities of compressed gases