49 CFR Appendix B to Part 172, Trefoil Symbol

Appendix B to Part 172 - Trefoil Symbol

1. Except as provided in paragraph 2 of this appendix, the trefoil symbol required for RADIOACTIVE labels and placards and required to be marked on certain packages of Class 7 materials must conform to the design and size requirements of this appendix.

2. RADIOACTIVE labels and placards that were printed prior to April 1, 1996, in conformance with the requirements of this subchapter in effect on March 30, 1996, may continue to be used.

1 = Radius of Circle -
Minimum dimensions
4 mm (0.16 inch) for markings and labels
12.5 mm (0.5 inch) for placards
2 = 1 1/2 Radii
3 = 5 radii for markings and labels
4 1/2 radii for placards.
[ 60 FR 50306, Sept. 28, 1995, as amended by Amdt. 172-143, 61 FR 20750, May 8, 1996]

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United States Code

Title 49 published on 2015-12-03

The following are ALL rules, proposed rules, and notices (chronologically) published in the Federal Register relating to 49 CFR Part 172 after this date.

  • 2017-01-18; vol. 82 # 11 - Wednesday, January 18, 2017
    1. 82 FR 5499 - Hazardous Materials: Volatility of Unrefined Petroleum Products and Class 3 Materials
      GPO FDSys XML | Text
      DEPARTMENT OF TRANSPORTATION, Pipeline and Hazardous Materials Safety Administration
      Advance notice of proposed rulemaking (ANPRM).
      Comments must be received by March 20, 2017.
      49 CFR Parts 171, 172, 173, 174, 177, 178, 179, and 180