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Interpretation Response #99-0152 ([Steptoe &; Johnson, LLP] [Mr. David H. Coburn])

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

Interpretation Response Details

Response Publish Date:

Company Name: Steptoe &; Johnson, LLP

Individual Name: Mr. David H. Coburn

Location State: DC Country: US

View the Interpretation Document

Response text:

September 23, 1999


Mr. David H. Coburn                         Ref. No. 99-0152
Steptoe &; Johnson, LLP
1330 Connecticut Avenue, NW
Washington, DC 20036-1795

Dear Mr. Coburn:

This is in response to your June 10, 1999, letter concerning liquefied gas loading in tank car tanks per the Hazardous Materials Regulations (HMR; 49 CFR, Parts 171-180). Specifically, you asked about the requirements in § 173.314(e) concerning the methods for verification of tank car content.

As per § 173.314 (e), the amount of liquefied gas loaded into a tank may be determined by either measurement or calculation.  If the measuremen 'option is used, the weight must be checked after disconnecting the loading lines by the use of proper scales.  Calculation by using the outage tables supplied by the tank car owners and the specific gravities as determined at the plant is allowed for liquefied petroleum gas, methylacetylene and propadiene mixtures, stabilized, dimethylamine, monomethylamine, and trimethylamine only.  If this option is used, then the computation must be checked by determination of specific gravity of product after loading.

Since anhydrous ammonia  is not listed, the method involving outage tables and specific gravities is not an option.

I hope this satisfies your request.



Delmer F. Billings
Chief, Standards Development
Office of Hazardous Materials Standards


Regulation Sections

Section Subject
173.314 Compressed gases in tank cars and multi-unit tank cars