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New Size Requirement for the Identification Number Marking in 2017

New Size Requirement for the Identification Number Marking in 2017

Unless excepted by regulation, a non-bulk package of a hazardous material in – or offered for – transportation must display its identification number as a marking. The four-digit identification number (preceded by “UN”, “NA”, or “ID” as appropriate) is found in column four of the Hazardous Material Table.  Other package markings, not to mention HazMat labels, will be required as well but I don’t intend to get into that here.  The purpose of this article is to bring to your attention a new (as of January 1, 2017) minimum size requirement for the height of the identification number marking on a non-bulk packaging.

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International and Domestic

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The citation for this regulation can be found in Title 49 of the Code of Federal Regulations part 172.301 (49 CFR 172.301). In paragraph (a) of this regulation the minimum height requirement for an identification number on a non-bulk packaging is established as follows.

AllMax Capacity of 30 L (8 gal)Max Capacity of 30 Kg (66 lb)Cylinder with Max Water Capacity of 60 L (16 gal)Max Capacity of 5 L (1.32 gal)Max Capacity of 5 Kg (11 lb)
12 mm (0.47") 6 mm (0.24") 6 mm (0.24") 6 mm (0.24") Size appropriate to size of package Size appropriate to size of package

Note 1: This is a minimum height requirement for the identification marking. There is no requirement for the width of the characters that make up the marking nor is there a requirement for the type of font used.

Note 2: This regulation went into effect on January 1, 2017 when the transitional exception from compliance at 49 CFR 172.301(a)(1)(i) ended.


There is one exception from the minimum height requirement remaining for certain permanently marked packagings. This exception is found at 49 CFR 172.301(a)(1)(ii). It’s conditions are summarized as follows:

  • Packaging is for domestic (within U.S.) transportation only.
  • Packaging manufactured prior to January 1, 2017.
  • Packaging is permanently marked with the identification number marking. Examples of an acceptable permanent marking include embossing or a heat stamp process.

If all of the above conditions are met, then the packaging may continue in service until the end of its useful life.

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The identification number is just one of the markings required on a hazardous material packaging. Many other markings have minimum size requirements as well, including but not limited to the following:

  • §173.3(c), each salvage packaging must be marked “SALVAGE” in letters at least 12 mm (0.5″) high.
  • §173.25(a)(4), the overpack is marked “OVERPACK” in letters at least 12 mm (0.5″) high.
  • §172.332(b)(1), an identification number for a bulk packaging on an orange panel must be 100 mm (3.9″) high and of black Helvetica Medium numerals.
  • §172.325(c), if both the identification number and the word “HOT” is displayed on a white-square-on-point display configuration, the word “HOT” must be in black letters having a height of at least 50 mm (2.0″).

There’s more, of course, but that will have to be for another article.  For now, make certain that the identification number marking on your non-bulk packagings of HazMat are in compliance with this new regulation.  And contact me if you require HazMat Employee training.