A Free UN Number Reference for HazMat Classrooms
No account, no paywall, no setup. Type a UN number, get the hazard class, packing group, ERG guide, and quantity exceptions — straight from 49 CFR §172.101. On any phone or projector.
If you teach hazmat — at a fire academy, a CDL school, a community college fire-science program, a shipping department, or an EHS team — you need a fast, reliable way for students to look up UN numbers without fighting a login screen or a clunky PDF. That's the whole point of UNLookup.
It's a quick-reference tool, not a textbook. It won't replace your curriculum or the regulations themselves. What it does is put the §172.101 essentials one search away, on whatever device is already in the room.
Built to get out of the way
How instructors use it
Live demos. Project the site, type a UN number, and walk through what each field means — hazard class, packing group, ERG guide, Limited and Excepted Quantity eligibility.
Student practice. Hand out a list of UN numbers and have students pull the classification and ERG guide themselves. Because there's no login, the whole class is working in seconds.
Field reference. Students keep it on their phones for ride-alongs, dock work, and on-the-job lookups after the course ends.
What each lookup shows
Each UN page surfaces the working essentials: hazard class and division, packing group, the assigned ERG guide number, Limited and Excepted Quantity eligibility, proper shipping name, and any marine-pollutant or special-provision flags. For the broader concepts behind those fields, send students to the hazard class chart, the packing groups explainer, the regulatory frameworks overview, or the ERG guide reference.
Where the data comes from
UNLookup's dataset is compiled from public regulatory sources — 49 CFR §172.101 (the U.S. Hazardous Materials Table) and the 2024 Emergency Response Guidebook published by PHMSA with Transport Canada and Mexico's SICT. It is 49 CFR-aligned by design, but it is a reference aid, not a certified training product or a substitute for the official regulations. Tell your students the same thing we tell everyone: verify against the current source before tendering a shipment.
Common questions
UNLookup is a reference utility for educational and informational use. It is not a certified training program and not a substitute for current editions of 49 CFR, the IATA DGR, the IMDG Code, or the Emergency Response Guidebook, nor for proper hazmat training and certification. Always verify against the official source applicable to your mode of transport before tendering a shipment. Regulations change; this page is updated periodically and may not reflect the most recent amendments.