When it comes to regulatory compliance, “hazardous” is an important term. Unfortunately, what is considered “hazardous” can be very confusing with the varying hazardous terms and definitions used across multiple regulatory agencies.

Overlapping Terminology

The fact is that different regulations have different definitions for similar terms, and these regulations are applied for different purposes. The same material can take on multiple descriptors—or not—depending on which regulations apply:

• Environmental Protection Agency (EPA) uses the term hazardous waste to protect human health and the environment (40 CFR 261 and 268).
• Department of Transportation (DOT) uses the term hazardous materials to ensure materials are managed safely in all modes of transport—air, road, marine, and rail (49 CFR 172).
• Occupational Safety and Health Administration (OSHA) uses the term hazardous substances and focuses on worker safety (29 CFR).

Sometimes, this terminology overlaps; sometimes it doesn’t. That is why it is critical to understand the differences between hazardous terms and to use each term appropriately—so you know what requirements apply.

EPA: Hazardous Waste

According to EPA, a hazardous waste is “a contaminated chemical or byproduct of a production process that no longer serves its purpose and needs to be disposed of in accordance with the EPA.”

Hazardous waste is generated from many sources, ranging from industrial manufacturing process wastes to batteries, and may come in many forms (e.g., liquids, solids, gases, and sludges). To determine whether a waste is considered “hazardous,” EPA has developed a flowchart identification process (pictured below).

EPA’s Resource Conservation and Recovery Act (RCRA) establishes the regulatory framework for managing hazardous waste. The degree of regulation that applies to each hazardous waste generator depends on the amount of hazardous waste produced.

Unless it is managed at the facility, hazardous waste generated must eventually be transported off site for disposal, treatment, or recycling. At this point, DOT regulations kick in for the transportation of freight, including the transport of RCRA hazardous waste.

DOT: Hazardous Material

DOT has the authority to regulate the transportation of hazardous materials under the Hazardous Materials Transportation Act (HMTA), which is overseen by the Pipeline and Hazardous Materials Safety Administration (PHMSA) division of DOT. A DOT hazardous material is defined as “a substance (gas, liquid, or solid) capable of creating harm to people, environment, and property.”

By definition, hazardous materials are capable of posing an unreasonable risk to health, safety, and property in commerce. This includes substances, wastes, marine pollutants, elevated temperature materials, and items included in DOT’s Hazardous Materials Table (HMT – 49 CFR 172.101) (e.g., laboratory chemicals, solvents, alcohol, acids, compressed gases, cleaners, pesticides, paints, infectious substances, radioactive materials). Note that anything excluded from the EPA’s Hazardous Waste Manifest requirements is not considered a hazardous waste by DOT when shipped but may be considered a hazardous material.  This is a tricky nuance but very important for shippers to understand. Correspondingly, DOT has rigorous training requirements.

Hazardous materials are legally defined by class, characteristic, and name:

• Class 1: Explosives
• Class 2: Gases
• Class 3: Flammable Liquid
• Class 4: Flammable Solids
• Class 5: Oxidizing Substances, Organic Peroxides
• Class 6: Poisonous (Toxic) and Infectious Substances
• Class 7: Radioactive Materials
• Class 8: Corrosives
• Class 9: Miscellaneous Dangerous Goods

OSHA: Hazardous Substance

Finally, OSHA defines a hazardous substance as “any substance or chemical that is a ‘health hazard’ or ‘physical hazard,’ including:

• Chemicals that are carcinogens, toxic agents, irritants, corrosives, sensitizers;
• Agents that damage the lungs, skin, eyes, or mucous membranes;
• Chemicals that are combustible, explosive, flammable, oxidizers, pyrophorics, unstable-reactive or water-reactive; and
• Chemicals which, in the course of normal handling, use, or storage, may produce or release dusts, gases, fumes, vapors, mists or smoke that may have any of the previously mentioned characteristics.”

Chemical hazards and toxic substances are addressed in several specific OSHA standards for general industry (29 CFR 1910 Subpart Z). OSHA’s Hazard Communication Standard (HCS – 29 CFR 1910.1200) is designed to ensure that information about chemical and toxic substance hazards in the workplace and associated protective measures is disseminated to workers and that the workers understand how to apply this knowledge to complete their job tasks safely.

Under HCS, manufacturers must provide a safety data sheet (SDS) for all hazardous substances they produce or import. The SDS conveys physical and health impacts, as well as procedures for exposures, spills, leaks, and disposal to employees and any downstream customers. Materials in transport must be properly labeled according to the HCS (i.e., flammable, explosive, radioactive), as well as meet DOT requirements.

In an additional OSHA program–Hazardous Waste Operations and Emergency Response (HAZWOPER)—all employees must be trained on emergency response, spill management, and risk minimization. This training covers:

• Code requirements​
• Hazard classes, risk identification, hazardous communication
• Site safety programs​
• Proper selection use of appropriate PPE and respiratory protection​
• Advanced spill management and emergency response procedures​
• Risk minimization, emergency management, and engineering controls​

The Overlap: An Example

Let’s see how these definitions come together in practice.

A DOT-regulated hazardous material that expires and becomes unusable might be regulated as a hazardous waste under EPA’s RCRA program. For example, if a company uses acetonitrile in their operations, when the company receives the acetonitrile as a product, it is transported to the company as a DOT Class 3 Flammable Liquid using a Bill of Lading as the shipping papers. If that same acetonitrile passes its expiration date and is unusable by the company, it must be shipped as a DOT Class 3 Flammable Liquid. 

Additionally, the generator (the company) must determine which waste codes are applicable. In this example, expired acetonitrile would have the waste code D001, indicating it is a flammable waste.  Because this was also an unused commercial chemical product, the expired acetone would have a waste code of U009 to comply with EPA hazardous waste regulations. Small and Large Quantity Generators (SQGs/LQGs) of hazardous waste would also have to ship the hazardous waste using a Hazardous Waste Manifest as the shipping paper versus a Bill of Lading.

A hazardous material or waste released to the environment in a quantity above a certain threshold, referred to as a Reportable Quantity, might be regulated as a hazardous substance for EPCRA reporting purposes. For example, if a tanker truck is delivering acetonitrile to the same facility, the acetonitrile is a hazardous material and meets the definition of a Class 3 Flammable Liquid. The Reportable Quantity for acetonitrile is 5,000 lbs. according to 49 CFR 172.102, Table 1. If the tanker truck is in an accident and 5,000 lbs. of acetonitrile spills (or is released to the environment), the trucking company must report the spill to the National Response Center to comply with EPA EPCRA regulations.

Importance of Training

As this example shows, there is much overlap between the different hazardous terminology and regulations—and getting it all correct is not always simple. This explains why rigorous training is required to meet compliance requirements for managing hazardous waste. OSHA, EPA, and DOT each have requirements for personnel who are working with chemicals, hazardous waste, or onsite emergency management activities:

• OSHA 1910.1200 (HazComm) requires all employees to be trained in label reading and SDS review for chemicals they may encounter in the workplace.
• OSHA 1910.120 (HAZWOPER) requires any employees who are in positions that may respond to chemical spills or emergencies onsite to be trained in chemical risk recognition, spill control basics, emergency response, and additional requirements depending on the level of response expected.
• DOT code (49 CFR 172.702) requires that any employee involved in the transportation (shipping or receiving) of hazardous materials must be trained and tested in general awareness, site-specific job functions, and transportation security.
• EPA code (40 CFR 266 and 273) requires that any employee taking part in chemical waste management (hazardous or universal) must be trained in proper waste disposal practices.

Making sure the right people get the right training will help ensure the organization understands hazardous terminology and correctly interprets the requirements related to hazardous substances the facility manufactures, uses, stores, or transports.