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Hazardous Materials: Marking

16 questions in the bank cover this topic. Everything below is drawn from the sources those questions cite.

Sources: 49 CFR 172.301, 49 CFR 172.302, 49 CFR 172.312, 49 CFR 172.313, 49 CFR 172.322, 49 CFR 172.324, 49 CFR 172.332

What you need to know

172.301(a)(1) requires the proper shipping name and the identification number with its UN, NA or ID prefix, both as given in the 172.101 Table.

Those two together are what a responder looks up.

each person who offers a hazardous material for transportation in a non-bulk packaging must mark the package with the proper shipping name and identification number (preceded by “UN”, “NA” or “ID,” as appropriate), as shown in the § 172.101 Hazardous Materials Table

49 CFR 172.301

172.301(a)(1) sets 12 mm generally, dropping to 6 mm for packages of 30 litres or 30 kg or less and cylinders of 60 litres water capacity or less, and to a size appropriate to the package below 5 litres or 5 kg.

None of the figures offered is the one the rule gives.

The identification number marking preceded by “UN”, “NA”, or “ID” as appropriate must be marked in characters at least 12 mm (0.47 inches) high.

49 CFR 172.301

172.302(b)(3) sets 6.0 mm width and 50 mm height for cargo tanks and other bulk packagings.

Rail cars require 100 mm height, and IBCs 25 mm.

Have a width of at least 6.0 mm (0.24 inch) and a height of at least 50 mm (2.0 inches) for cargo tanks and other bulk packagings.

49 CFR 172.302

172.302(d) keeps the marking on an emptied bulk packaging unless a listed exception applies.

Residue and vapour mean an empty tank is still a hazard, which is why 392.10 also makes empty cargo tanks stop at railroad crossings.

Each bulk packaging marked with a proper shipping name, common name or identification number as required by this subpart must remain marked when it is emptied unless it is—

49 CFR 172.302

172.312(a)(2) requires them on two opposite vertical sides pointing upright, in black or red on a contrasting background.

177.834(b) then requires the package to stay in that position throughout transport.

Legibly marked with package orientation markings that are similar to the illustration shown in this paragraph, on two opposite vertical sides of the package with the arrows pointing in the correct upright direction.

49 CFR 172.312

172.312(b) prohibits other arrows on liquid hazmat packages, because an arrow on such a package must mean one thing only.

An ambiguous arrow could get a drum loaded on its side. Not on a package containing a liquid hazardous material.

Arrows for purposes other than indicating proper package orientation may not be displayed on a package containing a liquid hazardous material.

49 CFR 172.312

172.324(b) requires RQ in association with the proper shipping name.

If the shipping name does not identify the hazardous substance, 172.324(a) also requires that name in parentheses. Marked in association with the proper shipping name.

The letters “RQ” must be marked on the package in association with the proper shipping name.

49 CFR 172.324

172.332(a) allows orange panels, the placard itself, or a white square-on-point under 172.336(b).

The orange panel is the one most drivers recognize beside a tank's placard. Any of the three displays is acceptable.

identification number markings must be displayed on orange panels or placards as specified in this section, or on white square-on-point configurations as prescribed in § 172.336(b)

49 CFR 172.332

172.322(b)(2) requires each end and each side at 3,785 litres, which is 1,000 gallons, or more.

Below that capacity 172.322(b)(1) requires only two opposing sides or two ends other than the bottom.

Be marked on each end and each side with the MARINE POLLUTANT mark if the packaging has a capacity of 3,785 L (1,000 gallons) or more.

49 CFR 172.322

172.322(e)(2) specifies a square-on-point with a black symbol and border at least 2 mm wide on a white or contrasting background.

Square-on-point is the same geometry as a placard, which is why it reads as hazard information. Any suitably contrasting background is acceptable in place of white.

The marking must be in the form of a square-on-point. The symbol and border must be black on a white or suitable contrasting background. The width of the border forming the square-on-point marking must be at least 2 mm.

49 CFR 172.322

172.313(c) requires the number on all four faces where 1,000 kg, which is 2,205 pounds, or more aggregate gross weight of the same material and identification number is loaded at one facility.

The same 1,000 kg threshold appears in the DANGEROUS placard rule. The threshold is aggregate gross weight of the material loaded at a single facility. Loaded at a single facility.

A transport vehicle or freight container containing a material poisonous by inhalation in non-bulk packages shall be marked, on each side and each end as specified in § 172.332 or § 172.336, with the identification number specified for the hazardous material in the § 172.101 table

49 CFR 172.313

172.301(a)(3) requires the identification number on all four faces for a vehicle carrying a single hazardous material in non-bulk packages, subject to conditions.

It does not apply to Class 1, Class 7, or materials for which identification numbers are not required.

A transport vehicle or freight container containing only a single hazardous material in non-bulk packages must be marked, on each side and each end as specified in the § 172.332 or § 172.336, with the identification number specified for the hazardous material in the § 172.101 Table

49 CFR 172.301

172.313(b) requires two opposing sides.

The marking is not required at all when the words Inhalation Hazard already appear on the label or placard itself.

A material poisonous by inhalation (see § 171.8 of this subchapter) shall be marked “Inhalation Hazard” in association with the required labels or placards, as appropriate, and shipping name when required. The marking must be on two opposing sides of a bulk packaging.

49 CFR 172.313

172.301(f) requires it near the proper shipping name.

LPG is normally given a smell deliberately so leaks are detectable; without that, a leak gives no warning, which is why the cylinder must say so. That is about a quarter of an inch.

No person may offer for transportation or transport a specification cylinder, except a Specification 2P or 2Q container or a Specification 39 cylinder, containing unodorized liquefied petroleum gas (LPG) unless it is legibly marked NON-ODORIZED or NOT ODORIZED in letters not less than 6.3 mm (0.25 inches) in height

49 CFR 172.301

172.301(a)(2) allows the omission where the EPA marking is already present, because that marking communicates the same thing.

The marking prescribed by 40 CFR 262.32.

The proper shipping name for a hazardous waste (as defined in § 171.8 of this subchapter) is not required to include the word “waste” if the package bears the EPA marking prescribed by 40 CFR 262.32.

49 CFR 172.301

172.302(f) grandfathers older markings where the key words match.

The example given is a tank car marked NITRIC OXIDE, which need not be remarked NITRIC OXIDE, COMPRESSED. The proper shipping name's key words are what count.

A bulk packaging marked prior to October 1, 1991, in conformance to the regulations of this subchapter in effect on September 30, 1991, need not be remarked if the key words of the proper shipping name are identical to those currently specified

49 CFR 172.302

Check yourself

Answers are in the practice test for this topic.