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Interpretation Response #99-0210 ([Marsulex, Inc.] [Sam Reeder, PhD])

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

Interpretation Response Details

Response Publish Date:

Company Name: Marsulex, Inc.

Individual Name: Sam Reeder, PhD

Location State: OH Country: US

View the Interpretation Document

Response text:

December 30, 1999


Sam Reeder, PhD                   Ref.  No. 99-0210
Quality Manager
Marsulex, Inc.
6800 W. Central Avenue
Suite L-1
Toledo, OH 43617

Dear Dr. Reeder:

This is in response to your letter and telephonic discussions with members of my staff concerning whether the use of two different primary hazard class labels and placards is permissible under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180).  Specifically, you inquire whether a POISON GAS label and the new INHALATION HAZARD label may be displayed for an export shipment that you identify as Sulfur dioxide, 2.3 (8), UN1079.  In addition, you inquire whether a highway transport vehicle or rail tank car may also display dual placards (old and new) for the poison inhalation hazard (PIH) material contained therein.  You intend to export PIH materials to Canada and it is your understanding that Transport Canada does not recognize U.S. mandated PIH communication requirements.

The answer to your questions is yes, the dual display of the old POISON GAS label or placard and the new INHALATION HAZARD label or placard is acceptable.  The old label and placard represent the hazard of the hazardous material contained in the package, transport vehicle or tank car and, therefore, their display are permitted under the conditions specified in §§ 172.401(a) and 172.502(a) respectively.

The effective date for use of the new Class 2 or Class 6 PIH label was October 1, 1999 (Docket HM-206).  The display of the PIH label with the words “INHALATION HAZARD” is optional, however, when the words are not displayed on the label, the shipment must be marked “INHALATION HAZARD” as specified in § 172.313. As you are aware, an interim final rule was recently published (September 16, 1999; HM-206D; 64 FR 50260), which authorizes, under certain conditions, a transition period for use of the old labels under the IMDG Code and the Canadian TDG Regulations.

For materials poisonous by inhalation, by all modes of transportation, the sole use of the old POISON GAS placard is permissible until October 1, 2001.  When the words “INHALATION HAZARD” do not appear on the placards, as, prescribed in § 172.540, the transport vehicle or rail car must be marked as prescribed in § 172.313.

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



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


Regulation Sections

Section Subject
172.502 Prohibited and permissive placarding