Interpretation Response #24-0105
Below is the interpretation response detail and a list of regulations sections applicable to this response.
Interpretation Response Details
Response Publish Date:
Company Name: A. Duie Pyle, Inc.
Individual Name: Rich Kaczynski
Location State: PA Country: US
View the Interpretation Document
Response text:
May 12, 2025
Rich Kaczynski
Safety Manager
A. Duie Pyle, Inc.
650 Westtown Road
P.O. Box 564
West Chester, PA 19381-0564
Reference No. 24-0105
Dear Mr. Kaczynski:
This letter is in response to your October 30, 2024 email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to marking and label visibility requirements as it relates to §§ 172.304(a)(3) and 172.406(f), respectively. Also, you provide several photographs of motor vehicle trailer loading configurations and ask whether they are deemed compliant with the referenced visibility requirements. Note that there are separate display and visibility requirements specific to UN identification number marking and placards on packages that are loaded in or on a transport vehicle, as well as placarding requirements for transport vehicles loaded with hazardous materials, that provide extra hazard communication (e.g., §§ 172.326(c), 172.331(c) and 172.504(c).
We have paraphrased and answered your questions as follows:
Q1. What is the definition of an "attachment" as referenced in §§ 172.304(a)(3) and 172.406(f)?
A1. The HMR does not define the term "attachment." The intent of the requirements in §§ 172.304(a)(3) and 172.406(f) is to ensure that required marking(s) and label(s) clearly communicate the hazard(s) presented within the package and that the display of the required marking(s) and label(s) is not obstructed by any additional markings, labels, or package attachments that may reduce the effectiveness of the required hazard communication.
Q2. Is a securement strap, or other freight securement devices commonly used in the transportation industry, used to meet the securement requirements stated in § 177.834(a) considered an attachment?
A3. Please refer to answer A1.
Q3. If a securement strap is considered an attachment, would the example provided be in violation of §§ 172.304(a)(3) and 172.406(f) since it partially covers the required hazard class labels and markings?
A3. No. The HMR do not specifically address the visibility of a package’s markings and labels when loaded onto or in a transport vehicle or in a freight container as it relates to other hazardous materials packages, other non-hazardous items aboard the vehicle or container, or means of securement (e.g., straps). In addition, specific means for securement and orientation of packages beyond § 177.834(a) and (b) are not specified in the HMR. However, loading, and securing packages in a transport vehicle in a manner that makes it difficult for emergency response personnel to identify potential hazards may delay emergency response efforts. Furthermore, difficulty in determining whether the package conforms to marking and labeling provisions may result in the frustration of the shipment by carrier or enforcement personnel.
Q4. If a cargo securement load bar is partially obscuring hazard class label(s) and marking(s)—as shown in the photograph provided—would this be a violation of §§ 172.304(a)(3) and 172.406(f)?
A4. Please refer to answer A3.
Q5. If other cargo is loaded in a trailer in front of or behind cargo that is already loaded in a trailer, but the cargo partially obscures hazard label(s) and marking(s)—as shown in the photograph provided—would this be a violation of §§ 172.304(a)(3) and 172.406(f)?
A5. Please refer to answer A3.
Q6. If the pallet or dunnage used to protect and secure hazardous material cargo in a trailer—as shown in the photograph provided—partially obscures the hazard class label and marking would this be a violation of §§ 172.304(a)(3) and 172.406(f)?
A6. Please refer to 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
172.304(a)(3), 172.326(c), 172.331(c), 172.406(f), 172.504(c), 177.834(a), 177.834(b)