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Interpretation Response #99-0196 ([Solvay Interox, Inc.] [Mark A. Feldman, Ph.D., CQ Mgr])

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

Interpretation Response Details

Response Publish Date:

Company Name: Solvay Interox, Inc.

Individual Name: Mark A. Feldman, Ph.D., CQ Mgr

Location State: TX Country: US

View the Interpretation Document

Response text:

August 25, 2000

 

Mark A. Feldman, Ph.D., CQ Mgr                 Ref   Nos.   99-0196 & 00-0033
Regulatory Affairs Manager
Solvay Interox, Inc.
P.O. Box 27328
Houston, TX 77227-7328

Dear Dr. Feldman:

I apologize for the delay in responding to your letters concerning the requirement in 49 CFR 173.3 1 (d)(1)(vi) to carefully inspect a frangible (rupture) disc in a pressure relief device prior to each hazardous material shipment.  This requirement has its origins in regulations of the Interstate Commerce Commission issued in 192 1. The wording of this requirement was most recently revised in a final rule published on September 21,1995, under RSPA’s Docket Nos.  HM- I 75A and 201 (60 Fed.  Reg. 49098).

As the language of § 173.31 (d)(1)(vi) states, the purpose of this type of inspection is to check "for corrosion or damage that may alter the intended operation of the device."  For that reason in response to a comment submitted in a separate rule-making proceeding under Docket No. HM-216 (61 Fed. Reg. 28666, 28671; June 5, 1996), we stated in the preamble that RSPA and FRA believe in order to fully inspect a rupture disc (both top and bottom), the disc must be removed from the safety vent device. It has been FRA's experience that a rupture disc may appear normal on the top side, but be severely damaged or corroded on the bottom side.

You and others have raised concerns about the language of the present rule and its application to persons that forward a loaded tank car received from another location or return a tank car with residue.  We anticipate initiating a rule-making in the near future to address these concerns.

Sincerely,

 

Edward T. Mazzullo
Director, Office of Hazardous
Materials Standards                 

173.31

Regulation Sections

Section Subject
173.31 Use of tank cars