Interpretation Response #24-0097
Below is the interpretation response detail and a list of regulations sections applicable to this response.
Interpretation Response Details
Response Publish Date:
Company Name: National Cargo Bureau
Individual Name: Graeme McPhee
Location State: NY Country: US
View the Interpretation Document
Response text:
December 30, 2024
Graeme McPhee
Director of Hazardous Materials
National Cargo Bureau
180 Maiden Lane
Suite 903
New York, NY 10038
Reference No. 24-0097
Dear Mr. McPhee:
This letter is in response to your October 2, 2024, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to marking cargo transport units (CTUs) with the appropriate United Nations (UN) identification number for poison inhalation hazard (PIH) materials. Specifically, you ask a series of questions regarding the requirement for PIH materials found in § 171.23(b) as it relates to the § 172.313(c) marking requirements for PIH materials when loaded on a CTU and provide us your understanding. Note that it is our understanding that the questions relate to loading of non-bulk packages at one facility. Further, you seek clarification regarding the marking of CTUs with the appropriate identification number for PIH materials.
We have paraphrased and answered your questions as follows:
Q1. You ask which identification number should be displayed for one shipment containing 800 kg of a PIH material in Hazard Zone A when combined with 1,200 kg of a PIH material in Hazard Zone B.
A1. In accordance with § 172.313(c), a CTU containing a PIH material in non-bulk packages shall be marked on each side and each end if it meets conditions in § 172.313(c)(1) and (c)(2). Although the CTU contains materials in different hazard zones, only the Hazard Zone B material is present in 1,000 kg or more; therefore, the identification number for the material in Hazard Zone B shall be marked when loaded at one facility in non-bulk packages.
Q2. You ask which identification number should be displayed for one shipment containing 1,100 kg of a PIH material in Hazard Zone A when combined with 1,200 kg of a PIH material in Hazard Zone B.
A2. In accordance with § 172.313(c)(3)(ii), if the CTU contains more than one material meeting the conditions of § 172.313(c)(3) and the materials are in both Hazard Zone A and B, the CTU shall be marked with the identification number for the Hazard Zone A material.
Q3. You ask whether a CTU that contains a PIH material in Hazard Zone A or Hazard Zone B with less than 1,000 kg would be a violation of the transport marking requirements if the identification number is displayed on all four sides of the CTU.
A3. For purposes of the HMR, the answer is no. There is no prohibition when displaying the identification number as a person is allowed to permissively mark a container provided the marking represents the hazard present in the CTU. For purposes of the International Maritime Dangerous Goods (IMDG) Code, Section 5.3.2.1—Display of UN Markings—specifies the conditions when to properly mark a CTU, yet it also does not prohibit permissive marking of a CTU.
Q4. You ask whether a CTU that contains only a PIH material in Hazard Zone C or Hazard Zone D with less than 4,000 kg would be a violation of the transport marking requirements if the identification number is displayed on all four sides of the CTU.
A4. The answer is no, see answer A3.
I hope this information is helpful. Please contact us if we can be of further assistance.
Sincerely,
Dirk Der Kinderen
Chief, Standards Development Branch
Standards and Rulemaking Division
171.23(b), 172.313(c), 172.313(c)(1), 172.313 (c)(2), 172.313(c)(3)(ii), 172.313(c)(3)