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Interpretation Response #06-0172

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

Interpretation Response Details

Response Publish Date: 08-25-2006
Company Name: Texas Railroad Commission   
Location state: TX    Country: US

View the Interpretation Document

Response text:

Aug 25, 2006


Mr. Jim Osterhaus                 Reference No. 06-0172
Texas Railroad Commission
P.O. Box 12967
Austin, TX 78711-2967

Dear Mr. Osterhaus:

This is in response to your letter requesting clarification of the emergency discharge control requirements under the Hazardous Materials Regulations (HMR; 49 CFR Parts 17 1-180) for non-metered cargo tank motor vehicles transporting liquefied compressed gas. Specifically, you ask whether these cargo tank motor vehicles may transport liquefied compressed gas if they do not have an “on-board” passive shutdown capability. The question is posed based on § 177.840(r), which you believe may except cargo tank motor vehicles from the shutdown requirement if a facility-provided transfer hose will be used.

The HMR require all cargo tank motor vehicles manufactured on or after July 1, 2001, and used to transport liquefied compressed gas to have an emergency discharge control capability as specified in § 173.3 15(n). For a cargo tank motor vehicle manufactured prior to July 1, 2001, and used to transport liquefied compressed gases, the required emergency discharge control equipment must be installed no later than the date of its first scheduled pressure test after July 1, 2001 (see § 180.405(m)). No cargo tank motor vehicle used to transport liquefied compressed gas may be operated after July 1, 2006 unless it is equipped with the appropriate emergency discharge control equipment (see
§ 173.315(n)(5)).

A cargo tank motor vehicle equipped with a specially designed hose assembly to meet the emergency discharge control requirements in § 173.3 15(n) may be unloaded using a delivery hose assembly provided by the receiving facility provided the conditions set
forth in § 177.840(r) are met. Note, however, that even a cargo tank motor vehicle that is unloaded using a facility hose must be equipped with emergency discharge control equipment appropriate to the material transported and the type of service in which the cargo tank motor vehicle is engaged.

I hope this information is helpful. Please contact this office if you have additional questions.



Hattie L. Mitchell
Chief, Regulatory Review and Reinvention
Office of Hazardous Materials Standards

173.315(n, 177.840(r)

Regulation Sections

Section Subject
§ 177.840 Class 2 (gases) materials