What the Haz? Hazmat, Hazardous Waste, HazCom, and HAZWOPER Explained
Hazmat means one thing to OSHA, something else to EPA, and something different again to DOT. Here's the full crosswalk of every 'haz' term and when each agency's definition applies.
⚡ In short: “Hazmat” means different things depending on which agency is asking. OSHA, EPA, and DOT each have their own definitions — and they borrow from each other. Here’s the crosswalk of every “haz” term (hazmat, HazCom, hazardous waste, hazardous substances, HAZWOPER) and when each applies.
A Deeper Dive Into the “Haz” Words
Every once in a while, we’ll get a call from someone looking for “hazmat” training. To you, the word hazmat may mean one thing — but to someone else it probably means something completely different. iSi’s mission is to help companies navigate compliance with EPA, OSHA, and DOT regulations. Once you start working with those regulations, you’ll find the definition of hazmat can be different for each agency and each situation.
⚠️ Why this matters: Mis-matching the “haz” term to the regulation is how training gets ordered wrong, programs miss scope, and inspections find gaps. A facility that signs up for “hazmat training” may actually need HAZWOPER, or DOT 49 CFR, or RCRA — all three are sold as “hazmat” in conversation, but each solves a different citation risk.
Each Agency Has Its Own Focus
Regulations and their definitions are typically written from the perspective of the agency’s mission:
- OSHA — safe and healthful working conditions for workers
- EPA — human health and the condition of the environment
- DOT — safe, efficient, sustainable, equitable movement of people and goods
Once you know the perspective for each, it’s easier to understand how regulations cross over or refer to one another.
Hazmat
Hazmat is a shortened version of “hazardous materials.” Each agency refers to it differently.
OSHA: The term can refer to hazardous materials or hazmat teams. A hazardous material is something that can be a health hazard or a physical hazard. A hazmat team is an organized group of employees who handle and control spills or leaks of hazardous substances. Individually trained members are called hazardous materials technicians. Many of these definitions come from the HAZWOPER standard.
DOT: Hazmat means “a substance or material capable of posing an unreasonable risk to health, safety, and property when transported in commerce.” It includes hazardous substances, hazardous wastes, marine pollutants, elevated temperature materials, materials listed in the Hazardous Materials Table, and materials meeting their criteria for hazard classes and divisions. A “Hazmat employee” is anyone who packages, prepares, physically transports, loads, unloads, designs packages for, fills out paperwork for, or ensures the safe transportation of hazardous materials.
EPA: A hazardous material is any item or chemical that can cause harm to people, plants, or animals when released by spilling, leaking, pumping, pouring, emitting, emptying, discharging, injecting, escaping, leaching, dumping, or disposing into the environment.
OSHA focused on people, DOT focused on transportation, EPA focused on the environment.
HazCom
Another shortened haz word: HazCom is short for the OSHA Hazard Communication Standard. This standard covers hazardous chemicals — any chemicals that are a physical or health hazard. HazCom deals with Safety Data Sheets (SDS), labeling, markings, training, and more.
EPA’s Emergency Planning and Community Right-to-Know Act (EPCRA) regulations refer to OSHA’s hazardous chemicals when determining which chemicals fall under EPCRA reporting requirements — those under the HazCom standard with SDSs are included.
Some companies also refer to HazCom training as “Employee Right-to-Know” training.
Hazardous Waste
The term hazardous waste comes from EPA’s Resource Conservation and Recovery Act (RCRA) hazardous waste regulations. There’s a lengthy determination process to determine if something qualifies. The criteria and roadmap are in the definition at 40 CFR 261.2.
EPA’s definition: “a waste with properties that make it dangerous or capable of having a harmful effect on human health or the environment. Hazardous waste is generated from many sources, ranging from industrial manufacturing process wastes to batteries, and may come in many forms, including liquids, solids, gases, and sludges.”
To qualify as hazardous waste, material must:
- Be discarded
- Be a solid waste (abandoned, recycled, inherently waste-like, or a military munition)
- Meet EPA’s hazardous waste criteria
This determination process must be completed and documented for each waste stream.
OSHA references hazardous waste in HAZWOPER, calling hazardous waste anything found to be hazardous waste by EPA definition or anything DOT calls a hazardous waste.
DOT defers to EPA’s definition and requires a hazardous waste manifest to ship hazardous waste. Hazardous waste is a hazardous material regulated for transportation — meaning when a vendor picks up your hazardous waste, your company is the shipper and therefore subject to all DOT hazmat regulations the same as any other hazardous material shipper.
Need help sorting out which “haz” training your team actually needs? iSi builds right-scoped training programs for HazCom, HAZWOPER, RCRA, and DOT hazmat and maps which applies to your operation. See our safety consulting services →
Hazardous Substances
All three agencies use the term “hazardous substance.”
EPA: “Any substance, other than oil, which, when discharged in any quantities into waters of the U.S., presents an imminent and substantial danger to the public health or welfare, including but not limited to fish, shellfish, wildlife, shorelines and beaches (Section 311 of the Clean Water Act); identified by EPA as the pollutants listed under 40 CFR Part 116.” Hazardous substances appear in CERCLA (Superfund), the Clean Water Act, the Clean Air Act, RCRA, and TSCA.
OSHA: A hazardous substance is whatever EPA CERCLA says it is, whatever DOT says is a hazardous material, whatever EPA says is a hazardous waste, or any biological/disease-causing agent that could lead to death, disease, behavioral abnormalities, cancer, genetic mutation, physiological malfunctions, or physical deformations in persons or their offspring.
DOT: A hazardous substance is a hazardous material listed in Appendix A when its single package exceeds the reportable quantity listed in the Appendix. Additional considerations apply for mixtures, solutions, and radionuclides.
HAZWOPER
HAZWOPER stands for Hazardous Waste Operations and Emergency Response. It’s found in the 1910 General Industry Standards under Subpart H, Hazardous Materials. An identical copy exists under the 1926 Construction Standards.
Three main goals of HAZWOPER:
- Rules for conducting cleanup operations at sites determined to be EPA RCRA hazardous waste cleanup sites, contaminated uncontrolled hazardous waste sites that EPA or another government agency has required to be cleaned up, or voluntary cleanups at those same types of sites
- Operations at treatment, storage, and disposal facilities (TSD) regulated by EPA RCRA
- Emergency response to releases of hazardous substances at any facility, any location
Being an OSHA regulation, HAZWOPER is about protecting workers and the public during cleanup. It uses nearly every “haz” term and integrates requirements from all three agencies:
- Materials cleaned up and containerized into drums must meet DOT transportation, RCRA hazardous waste, and OSHA safety regulations
- Waste must be transported per DOT regulations
- Self-contained breathing apparatuses must comply with DOT standards
- DOT’s Emergency Response Guidebook is frequently referenced
- A company’s EPA contingency plan can serve as part of the emergency response plan to avoid duplication
On the EPA side, because OSHA regulations don’t apply to state and local governments, EPA adopted HAZWOPER into 40 CFR 311 to apply to those governments and others not covered by a state OSHA-approved plan. EPA’s emergency spill provisions also trigger reporting requirements, response plans, and training to protect the environment from hazardous waste spills, oil spills, pipeline leaks, and chemical releases.
Conclusion
This isn’t an exhaustive list of haz references, but it should give you a picture of how the terms and related rules can be so different in some cases and so intertwined in others. The right “haz” word depends on the situation — so if you call us asking for hazmat training, expect a lot of questions about what your end goal actually is.
💰 What ordering the wrong training costs: A facility that signs up for “hazmat” and gets basic HazCom when it actually needed DOT 49 CFR ends up with a compliant SDS program and a non-compliant shipping program — the kind of gap a single DOT inspection turns into $30K–$100K+ in civil penalties, plus potential loss of hazmat shipping authority.
Frequently Asked Questions
Q: How do EPA, OSHA, and DOT define hazardous materials differently?
OSHA focuses on worker safety and defines hazardous materials as substances posing health or physical hazards. EPA focuses on environmental protection and defines hazardous materials as substances that could harm people, plants, or animals when released. DOT focuses on transportation and defines hazardous materials as substances posing unreasonable risk during transport in commerce.
Q: What is a hazardous waste and who defines it?
EPA defines hazardous waste as waste with properties making it dangerous or harmful to human health or the environment. Material must be discarded and a solid waste, then meet EPA’s hazardous waste criteria (40 CFR 261.2). OSHA and DOT defer to EPA’s definition. Each waste stream requires a documented determination.
Q: What is HAZWOPER and what does it cover?
HAZWOPER (29 CFR 1910.120) is the OSHA standard covering RCRA hazardous waste cleanup, TSD facility operations, and emergency response to hazardous substance releases. It incorporates EPA, OSHA, and DOT requirements — making it the rare single standard that touches all three agencies.
Q: When does a facility need to comply with all three agencies?
When hazardous waste is shipped, it becomes DOT-regulated in transportation. Cleanup activities bring HAZWOPER (which combines all three). Facilities generating hazardous waste must comply with EPA RCRA (handling/disposal), OSHA worker safety, and DOT transportation rules simultaneously.
Q: What’s the difference between HazCom and HAZWOPER?
HazCom (29 CFR 1910.1200) is about chemical labeling, SDS access, and employee right-to-know for any hazardous chemical in the workplace. HAZWOPER (29 CFR 1910.120) is about cleanup and emergency response operations involving hazardous substances. Nearly every facility needs HazCom; only facilities performing cleanup or emergency response need HAZWOPER.
Q: If a vendor picks up my hazardous waste, who’s the DOT “shipper”?
You are. The generator is the DOT shipper even when a third-party transporter does the driving — meaning your facility needs DOT hazmat training, proper manifesting, and all the associated recordkeeping.
Need help mapping which “haz” rules apply to your operation? Run the 60-second Compliance Gap check or get a scoped proposal from our team.
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