# URS — Hazardous Materials Safety Interpretation - **operation:** document - **citation:** 09-0224 - **title:** URS — Hazardous Materials Safety Interpretation - **source type:** guidance - **agency:** Pipeline and Hazardous Materials Safety Administration - **status:** guidance - **official:** true - **published on:** 2009-10-14 - **effective on:** Not available - **summary:** 09-0224 response to URS concerning 172.334, 172.502. - **machine formats:** - **json:** https://regulus.evalyn.ai/document/phmsa-interpretation-09-0224.json - **markdown:** https://regulus.evalyn.ai/document/phmsa-interpretation-09-0224.md - **app url:** https://regulus.evalyn.ai/document/phmsa-interpretation-09-0224 - **source url:** https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/legacy/interpretations/Interpretations/2009/090224.pdf **body:** <<>> U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration 1200 New Jersey Ave,S.E. Washington, D.C. 20590 OCT 1 4 20U9 Ms. Erin N. Jarman Environmental Scientist 1600 Perimeter Park Drive Suite 400 Morrisville, NC 27560 Ref. No. 09-0224 Dear Ms. Jarman: This responds to your October 1,2009 letter requesting clarification concerning cargo tank marking and placarding requirements under the Hazardous Materials Regulations (HMR, 49 CFR Parts 171 -1 80). Your questions are paraphrased and answered as follows: Q1. When a cargo tank is cleaned and purged of residue and vapor, may the placard representing the hazardous material previously contained in the cargo tank remain on the vehicle? Al. No. Section 172.502(a) prohibits the display of placards on any packaging, freight container, unit load device, motor vehicle, or rail car unless the material being offered for transportation or transported is a hazardous material and the placard represents a hazard of the hazardous material being offered or transported. 42. When a cargo tank is cleaned and purged of residue and vapor, is it permissible to display four zeros in place of the UN number of the hazardous material previously contained in the vehicle? Or is it correct and preferred to flip the UN number marking section of the placard to display all blanks (i.e., no numerals)? A2. Section 172.334(b)(3) prohibits the display of a UN identification number unless the vehicle contains the hazardous material associated with that UN identification number. It is the opinion of this Office that using four zeros in lieu of blank spaces in the UN number marking section of a placard could cause confusion for emergency responders in the event of <<>> an incident and, in keeping with the intent of the regulations, is prohibited. Therefore, it would be correct to flip the UN number marking section of the placard to display all blanks (i.e., no numerals). I hope this answers your inquiry. If you need further assistance, do not hesitate to contact this Office. hief, Standards Development f Hazardous Materials Standards <<>> October I, 2009 Mr. Edward T. Mazzullo Director, Office of Hazardous Materials Standards U.S. DOTPHMSA (PHH-1 0) 1200 New Jersey Avenue, SE East Building, 2nd Floor Washington, DC 20590 Dear Mr. Mazzullo: I am writing to you with regards to a clarification of the permissive/prohibitive marking and placarding regulations for cargo tanks pursuant to 49 CFR §172.334(b)(3) and 49 CFR §172.502(a). Specifically, a cargo tank which previously contained a hazardous material has been cleaned and purged of residue and vapor and is therefore considered "empty" per 49 CFR 8173.29. The language in 49 CFR §172.502(a)(l)(ii) states the following: "Except as provided in paragraph (b) of this section, no person may affix or display on a packaging, freight container, unit load device, motor vehicle or rail car any placard described in this subpart unless the placard represents a hazard of the hazardous material being offered or transported." My questions are as follows: 1) When a cargo tank has been cleaned and purged of residue and vapor, is it permissible to leave the placard which represented the hazard prior to cleaning and purging on the vehicle? Or must the placard representing the hazard present prior to cleaning be removed, obscured, or otherwise be made not visible during transportation? 2) Under 49 CFR § 172.334(b)(3), a transport vehicle is prohibited from displaying an identification number unless the vehicle contains the hazardous material associated with that identification number. Since "0000" is not a valid UN identification number found in the hazardous materials table at 49 CFR 8 172.101, would it be permissible to display four zeros in place of the UN number? Or would the correct and preferred method be to flip the UN number marking section of the placard to display all blanks (i.e., no numerals)? Per a telephone conversation on August 27,2009 with Ms. Susan Gorsky of your office, it was her opinion that the display of "0000" in lieu of blank spaces in the UN number marking section of a placard could cause confusion for emergency responders in the event of an incident and in keeping with the intent of the regulations, would be a prohibited practice. Thank you in advance for your assistance. I look forward to your response. Sincerely, Erin N. Jarman Environmental Scientist URS Corporation 1600 Perimeter Park Drive Suite 400 Morrisville, NC 27560 Tel: 919-461-1478 Erin-Jarman@urscorp.com - **truncated:** false - **body characters:** 4579