​The Importance & Meaning of Hazard Labels

Shippers should treat every item they send out with the care it needs, and the best possible version of that care. If they are fragile, use the right cushioning, materials, and packaging to prevent damage during transit.

When it comes to hazardous materials, though, you cannot afford to skimp on quality. If anything happens to them, the consequences can be disastrous and deadly. Hazardous labels are a crucial part of maintaining safety during shipping. Read on to learn more about deciphering them and using them correctly.

What are Hazard Labels?

Hazard labels serve a similar function for packages and vehicles containing hazardous materials. These bright, colorful, diamond-shaped tags are designed to communicate one important message: handle with extreme care and caution. The numbers and symbols provide further details on proper handling for those who understand them, namely shippers and truckers.

They come in two forms. Some labels are meant to be stuck on boxes and other containers. Placards must be placed on trucks, in full view where other vehicles on the road can see them. Either way, shipping workers are required to only use hazard labels approved by the US Department of Transportation.

What are the 9 Hazard Classes?

The US Code of Federal Regulations Title 49 (49 CFR) separates all hazardous materials into nine categories, which may be further separated into several divisions. Each hazard class corresponds to a different type of hazard. Each one also gets its own label, with its own distinct color and the class number on the bottom corner. Here is a brief guide. Please note that hazmat labels and placards may differ in certain details.

Class 1

The first class is reserved for the most concerning threat of them all: explosive hazards. Materials in this class may react in certain ways that instantly unleash destructive forces, with little chance to detect, prevent, contain, or escape it.

These labels are orange. Divisions 1.1A, 1.2B, and 1.3C feature a graphic of lines and bits bursting from a cracked circle. Divisions 1.4, 1.5 (which uses the term “Blasting Agent” rather than “Explosive” for clarity), and 1.6 feature those numbers in a larger font.

Class 2

If specific conditions can cause a material to produce a dangerous gas, it belongs to Class 2. Five different labels/placards represent the three divisions and the class as a whole:

Flammable Gas (2.1) — red with a flame symbol

Non-Flammable Gas (2.2) — green with a graphic of a compressed gas cylinder

Toxic Gas (2.3) — white with skull and crossbones

Inhalation Hazard — white with skull and crossbones contained within its own black diamond on the top corner

Oxygen — yellow with a ring on fire

Depending on the nature of the hazards in the materials being transported, more than one of these may be used in combination.

Class 3

Class 3 is exclusively home to flammable and combustible liquids, with no further divisions. The associated color is red. There is only one label: “Flammable Liquid,” with an image of fire. There are three placards, all identical to the label except for the words: “Flammable,” “Combustible,” and “Fuel Oil.”

Class 4

With gases and liquids covered, Class 4 finishes the series with flammable solids. All three divisions have their own label/placard. While all three share the flame icon, their color schemes are all different:

Flammable Solid (4.1) — alternating crimson and white columns

Spontaneously Combustible (4.2) — white top half and crimson bottom half

Dangerous When Wet (4.3) — Light blue all over

Class 5

Oxidizers and organic peroxide both feature oxygen as a key ingredient. Both are vulnerable to the reaction known as oxidation, which can start fires. Both are lumped into Class 5 together as Divisions 5.1 and 5.2, respectively.

The labels and placards look different from each other. The oxidizers design is all yellow, and the image is a ring whose top part is ablaze. Meanwhile, the one for organic peroxide is crimson on top and yellow on bottom. Its image is the familiar flame. As with all hazmat labels and placards, the names are visible for greater clarity.

Class 6

Class 6 only breaks down into two divisions: poisonous materials (6.1) and infectious substances (6.2). Despite this, shipments of these materials may require any of four different hazmat placards. The designs include Poison, Toxic, Inhalation, and PG III (short for Packing Group III, which encompasses substances representing “low danger”).

One design is unique to the hazmat labels. This is likely because it comes with a warning that must be written in text too small for drivers to see on a truck. The big text identifies the contents of the package as “Infectious Substance.” The small text reads, in full, “In Case of Damage or Leakage, Immediately Notify Public Health Authority.”

Class 7

Only select groups of shippers will ever need to work with hazardous materials that fall under Class 7. This designation is for radioactive materials, such as uranium and certain ores. There are no divisions, so there is only one placard: mostly white, with a yellow section at the top containing the international radioactivity symbol.

On the other hand, the labels come in four distinctive designs. “Radioactive I” looks identical to the placard, but the section with the symbol is also white. “Radioactive II” and “Radioactive III” look identical to the placard, albeit with boxes in the bottom half for “Transport Index.” The last one, which reads “Fissile,” is white all over, with a line across the middle and a box for “Criticality Safety Index.”

Class 8

Acids, lye, and certain batteries and dyes all have corrosive properties. With the wrong reactions and insufficient packaging, they may melt through metal, skin, and more. Class 8 materials require exceptional care, but not exceptional effort to mark.

One label/placard design is all you need. It is white on top, black on bottom, with ominous graphics of test tubes dripping holes into a black bar and a pair of hands.

Class 9 & More

For everything else, there is Class 9. The miscellaneous category cannot have divisions, so as with Class 8, only one design is needed. The bottom half is white. The other half has black columns jutting from the top, interrupting the white, and stopping at an invisible line in the middle.

Speaking of miscellaneous, there are several other hazard labels out there that do not correspond to a specific class or division. One notable placard for trucks features red triangles enclosing a white band with text that simply reads “Dangerous.” Others communicate various details that shippers and vehicle operators may find useful.

Where Do I Put Them?

One should always keep visibility in mind when applying any labels, but hazard labels are especially important. Handling hazardous materials without being aware of it is a recipe for catastrophe. To avoid such a risk, hazard labels should be placed beside the UN number and proper shipping name. If the package is large enough, all this information should be on the same side — and not on the bottom.

Hazmat placards are not much bigger than ordinary hazmat labels. However, the bulk packaging and truck holds on which you affix them are larger. To get the vital message across, 49 CFR requires shipping workers to place them on all sides. Drivers on any side of the transport vehicle can recognize the danger and move cautiously.

No matter what hazard labels you may need, you can find them here at Quick Pak Inc. Call us at 813 242 6995 or sales@quickpakinc.com

We also offer a diverse selection of hazmat placards for vehicular operations.