Class 7 sits in its own regulatory universe: overseen by the NRC and DOT, gated by package types, transport indices, and route restrictions most carriers will never touch.
A Different Regulatory Universe
General information, not legal advice. Most Hazmat freight lives under DOT and the nine standard hazard classes. Class 7, radioactive material, sits inside that framework but answers to a second master: the Nuclear Regulatory Commission. Between NRC oversight, package-type rules, transport indices, route restrictions, and driver training requirements that go well beyond a standard Hazmat endorsement, Class 7 is its own discipline. Most carriers will never touch it, and that's the right answer for them.
If your freight includes medical isotopes, industrial radiography sources, density gauges, or research isotopes, here is what the regulatory shape actually looks like.
Type A vs. Type B Packages
Class 7 packaging tiers map to the activity level of the contents and the survivability requirements of the package itself.
Type A
Type A packages are designed to survive normal transport conditions (drops, stacking, weather) without releasing contents or losing shielding. They cover most medical isotopes and lower-activity industrial sources. The package itself is engineered to a DOT specification, but it does not have to survive an accident scenario.
Type B
Type B packages are designed to survive accident conditions: a 9-meter drop onto an unyielding surface, a 1-meter puncture drop, a 30-minute fully engulfing fire, and water immersion. They are heavy and required for higher-activity contents: spent fuel components, large industrial sources, and certain research material. Higher-activity package designs (Type B and fissile) are individually approved by the NRC or DOT. Type B(U) is unilaterally approved by the country of origin; Type B(M) requires multilateral approval for international transport.
Picking the wrong package tier isn't a fine; it's a refusal-of-shipment by any compliant carrier and a notification event for the regulator.
NRC 10 CFR Part 71
Part 71 is the operating manual: it governs package design, certification, approval, recordkeeping, and the handoff between NRC authority and DOT transport rules (49 CFR Part 173 Subpart I). The shipper is responsible for classifying material correctly, selecting the right package, certifying the package's integrity, marking and labeling, and preparing the shipping papers. The carrier is responsible for operating under DOT placarding and routing rules and maintaining the chain of custody.
The shipper-carrier interface matters. A carrier that accepts a Class 7 shipment without verifying the package classification, the transport index, and the driver's qualifications is operating outside its compliance envelope, even if nothing goes wrong on the lane.
Transport Index and Criticality Safety Index
Two numbers govern how Class 7 packages can be loaded and transported.
- Transport Index (TI) is a measure of the external radiation level at one meter from the package surface, expressed as mrem/hr. It dictates labeling category (White-I, Yellow-II, Yellow-III), how many packages can be co-loaded, and what separation distances apply from people and undeveloped film.
- Criticality Safety Index (CSI) applies to fissile material and limits aggregate loading on a single conveyance to a maximum sum value.
A driver and dispatcher who can't read these numbers off the shipping paper and translate them into a loading plan have no business handling the lane. Most rejections at the dock come from misreading the TI and exceeding aggregate transport limits.
Route Restrictions
Class 7 high-route-controlled quantity (HRCQ) shipments are subject to written route plans, advance notification to state regulators, and specific routing requirements that prefer Interstate highways and avoid population centers where practical. State-by-state variation exists, and some states require explicit pre-approval. A dispatcher building a Class 7 lane plans the route first and the freight second.
Some Class 7 shipments also trigger DOT hazmat security plan requirements, depending on type and quantity. Check the thresholds with your compliance team.
Driver Training
A standard CDL with Hazmat endorsement is the floor, not the ceiling. Class 7 drivers should have:
- Documented training on Subpart I packaging recognition.
- Specific instruction on TI and CSI math.
- Emergency response training for radiation incidents (what to do, who to call, exclusion-zone basics).
- Familiarity with the specific package types they'll be hauling, Type A handling differs operationally from Type B.
Annual recurrent training is the minimum cadence. Carriers serious about Class 7 do it more often.
Why Most Carriers Decline
Class 7 is a low-volume, high-liability lane. The insurance premium is real, the training overhead is real, and the regulatory exposure is real. Carriers that take it on do so because they've built the program intentionally, not because they accepted the load and figured it out after the fact.
If you ship regulated freight and want a carrier that builds the program intentionally, our Hazmat service handles hazmat loads case by case through qualified partner carriers.
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