This post was sponsored by Lion Technology, Inc.

When the EHS world speaks of something being “hazardous,” it is not enough to know only one definition of the word. Regulatory agencies such as the U.S. Department of Transportation (DOT), EPA, and OSHA use terms like hazardous materials, hazardous wastes, hazardous substances, and hazardous chemicals. Each describes a different class of regulated article and carries its own connotation of what makes the thing it describes “hazardous.”

This blog post considers four sets of regulations and break down their objectives, how each set of regulations works, and how they impact the class of article they cover.

Hazardous Materials

The Hazardous Materials Regulations (HMR), formulated by DOT, standardize the transport of hazardous materials in the United States. Because transport lasts for a relatively short period of time, DOT’s criteria for hazardous materials focus on acute hazards.

Generally speaking, DOT uses nine numbered hazard classes to define a material as “hazardous.” The first eight classes are explosives (class 1), compressed gases (class 2), flammable liquids and solids (classes 3 and 4, respectively), oxidizers (class 5), poisons (class 6), radioactive material (class 7), and corrosives (class 8).

The ninth hazard class, Miscellaneous Hazards, is used for materials that do not meet the criteria of classes 1–8, but still pose hazards in transport. Lithium batteries are one example.

Hazardous Waste

Among other responsibilities, EPA works to protect human and environmental health from the hazards associated with short- and long-term management of hazardous waste. To achieve this, EPA requires facilities to carefully manage waste products with certain characteristics, or kinds of wastes that EPA lists in its regulations.

The four waste characteristics EPA focuses on are ignitability, corrosivity, reactivity, and toxicity.

EPA’s listed hazardous wastes, enumerated in the Resource Conservation and Recovery Act (RCRA) regulations in 40 CFR 261.31, 261.32, and 261.33, include:

• Wastes from non-specific sources generated by industrial or manufacturing processes (F List)
• Wastes generated by specific industries (K List)
• Unused, discarded commercial chemical products (P and U List)
  

Unlike the characteristics listed above, which require testing to identify, the listings are descriptive. If your waste meets a description found on these lists, it is a hazardous waste (unless specifically excluded).

Hazardous Substances

Under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), EPA also requires facilities to report releases of hazardous substances to the environment.

EPA assesses the threat of each substance it regulates and assigns it a reportable quantity (RQ), which can be as low as one pound. When an unauthorized or unpermitted release occurs in excess of the RQ, the facility must report it immediately.

Hazardous Chemicals

Finally, OSHA regulates the use of hazardous chemicals in the workplace. Because an employee may work with the same chemical for many years, OSHA considers both acute and chronic hazard criteria.

OSHA’s hazard communication regulations in 29 CFR 1910.1200 focus on some of the same hazards we’ve discussed already: explosives, flammables, corrosives, and poisons. Other OSHA hazard criteria include human health risks like skin corrosives, eye irritants, reproductive toxins, and carcinogens.

Overlap in Hazardous Terminology

Even when different regulatory agencies use the same vocabulary to describe hazardous materials, wastes, or substances, the definitions can vary depending on what set of regulations you are reading.

When DOT uses the term “hazardous waste,” for example, they mean those wastes that require the use of the Hazardous Waste Manifest for transportation—a narrower definition than the one from RCRA detailed above. DOT also uses the term “hazardous substances”—but it only applies when a substance’s RQ is present in a single package.

When you need to determine which regulations apply to your hazardous articles, common sense can only take you so far. To make an accurate determination, you must carefully examine each agency’s specific definition and criteria to determine if and how your “stuff” is regulated.