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

Interpretation Response #15-0024 ([Hazardous Materials Response Unit] [Officer Daniel Voelker])

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

Interpretation Response Details

Response Publish Date:

Company Name: Hazardous Materials Response Unit

Individual Name: Officer Daniel Voelker

Location State: AZ Country: US

View the Interpretation Document

Response text:

September 08, 2015

Officer Daniel Voelker
Arizona Department of Public Safety
Hazardous Materials Response Unit
2102 W. Encanto Blvd, Mail Drop 4011
Phoenix, AZ 85009

Ref. No. 15-0024

Dear Officer Voelker:

This responds to your February 2, 2015 email requesting clarification of placarding requirements under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you request further clarification on the use of the DANGEROUS placard as described in interpretation letter Ref. No. 14-0031.

Letter Ref. No. 14-0031 addresses a scenario in which a transport vehicle containing non-bulk quantities of Class 3 flammable liquid and combustible liquid displays a DANGEROUS placard instead of the separate placards specified for each of the materials. PHMSA’s stated position in the letter is that this is acceptable; and furthermore, a COMBUSTIBLE placard is not required for combustible liquids in non-bulk packaging (§ 172.500(b)(6)). Additionally, a placard may be displayed for a hazardous material, even when not required, provided the placarding is carried out in conformance with Part 172, Subpart F.

You request reconsideration of our position in letter Ref. No. 14-0031 and believe use of the DANGEROUS placard is not authorized because there is only one category of hazardous material in Table 2 of § 172.504 requiring placards. Therefore, it is not permissive placarding under § 172.502(c) because it does not otherwise conform to the placarding requirements of the Subpart; specifically § 172.504(b).

Your understanding is not correct. The response in letter Ref. No. 14-0031 is consistent with the HMR requirements in Part 172, Subpart F. The general placarding requirements in § 172.504(a) require each bulk packaging, freight container, unit load device, transport vehicle or railcar containing any quantity of hazardous material to be placarded with the placards specified in Tables 1 and 2 of that section. Table 2 includes a placard for both flammable and combustible liquids. While § 172.500(b)(6) provides an exception from placarding for combustible liquids in non-bulk packagings, a placard may be displayed for a hazardous material, even when not required in accordance with permissive placarding described in § 172.502(c). Similarly, a DANGEROUS placard may be displayed for two or more categories of hazardous materials that have different placards specified, even when neither is required to be placarded.

I hope this answers your inquiry. If you need additional assistance, please contact this Office at 202-366-8553.



Dirk Der Kinderen
Acting Chief, Standards Development Branch
Standards and Rulemaking Division

172.500(b)(6), 172.504, 172.502(c), 172.504(b), 172.504(a)

Regulation Sections

Section Subject
172.500 Applicability of placarding requirements
172.502 Prohibited and permissive placarding
172.504 General placarding requirements