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Interpretation Response #12-0183 ([Bureau of Explosives, TTC, Inc] [Mr. Paul Draper])

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

Interpretation Response Details

Response Publish Date:

Company Name: Bureau of Explosives, TTC, Inc

Individual Name: Mr. Paul Draper

Location State: TX Country: US

View the Interpretation Document

Response text:

October 31, 2012




Mr. Paul Draper
Chief Inspector
Bureau of Explosives, TTC, Inc.
205 Kayla Lane
Longview, TX 75602

Ref. No.: 12-0183

Dear Mr. Draper:

This responds to your August 19, 2012 letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to petroleum sour crude oil in bulk packaging. You ask about a shipment of petroleum sour crude oil containing hydrogen sulfide (i.e., sour crude oil) in sufficient concentration that the vapors may present an inhalation hazard, thus requiring the material to be marked, labeled, tagged, or signed to warn of the toxic inhalation hazard as required by § 172.327. Specifically, you ask if the Pipeline and Hazardous Materials Administration (PHMSA) defines the term "sufficient concentration" for the purpose of determining whether the petroleum sour crude oil must be marked as an inhalation hazard.

The answer is no. PHMSA does not establish a concentration level for hydrogen sulfide in petroleum sour crude oil in order to determine if the vapors are an inhalation hazard. To determine whether petroleum sour crude oil presents an inhalation hazard, it must be tested to determine if the material meets division 2.3 (gas poisonous by inhalation) as defined in § 173.115(c) of the HMR. If the vapors in the petroleum sour crude oil meet the definition of a division 2.3 material, you must follow the marking and labeling requirements of § 172.327.

I trust this satisfies your inquiry. Please contact us if we can be of further assistance.



T. Glenn Foster
Chief, Regulatory Review and Reinvention Branch
Standards and Rulemaking Division

173.115, 172.327

Regulation Sections

Section Subject
172.327 Petroleum sour crude oil in bulk packaging
173.115 Class 2, Divisions 2.1, 2.2, and 2.3-Definitions