USA Banner

Official US Government Icon

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure Site Icon

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Interpretation Response #04-0166 ([Hogan & Hartson L.L.P.] [Ms. Christine Arcari])

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

Interpretation Response Details

Response Publish Date:

Company Name: Hogan & Hartson L.L.P.

Individual Name: Ms. Christine Arcari

Location State: DC Country: US

View the Interpretation Document

Response text:

May 4, 2005


Ms. Christine Arcari                Reference No. 04-0166
Environmental Specialist
Hogan & Hartson L.L.P.
555 13th Street, NW
Washington, DC 20004

Dear Ms. Arcari:

This responds to your e—mail requesting clarification of the packaging requirements for insoluble solids pack in liquids under the Hazardous Materials Regulations (HMR; 49 CFR Parts l71-180).  Specifically, you ask whether an insoluble solid such as Phosphorus, white or yellow (UN1381) must be placed in a specification packaging (1A2, removable head steel drum) rated for both solids and liquids when packaged under water as prescribed in § 173.188. I apologize for the delay in responding and any inconvenience it may have caused.

The answer is no. As prescribed in § 173.188(a) (2;, white or yellow phosphorus may be placed in water in a removable head steel drum (lA2) with a capacity not over 115 L (30 gallons) As specified in the § 173.188 introductory text, the drum must be rated at the Packing Group I performance level and, because the drum contains a material that remains in a liquid phase when transported, the drum need only be tested for liquids. A drum containing a pyrophoric material such as white or yellow phosphorus must contain sufficient water so that the material remains covered in transportation regardless of orientation.

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
173.188 White or yellow phosphorus