IATA vs DOT: What Changes When You Ship Radioactive Material by Air

Why Understanding the Differences Matters

Most radioactive material shippers in the United States learn DOT 49 CFR first. The HMR is the domestic ground shipping framework, and for many shippers it is the only framework they use day-to-day. But the moment a shipment needs to go by air, the IATA DGR becomes the governing document, and understanding what changes — and what does not — is the difference between a smooth handoff and a rejected shipment at the cargo counter.

I have worked with a nuclear pharmacy that shipped medical isotopes by ground daily without a single issue. They had their DOT procedures down cold — shipping papers, labels, placards, everything. Then a hospital across the country needed an emergency delivery, and the only option was air. The shipping supervisor pulled out the same shipping paper template they used for ground, wrote the activity in millicuries, and sent the package to the airport. The airline rejected it immediately. No DGD, wrong units, and the shipper had no idea what a DGD even was. That experience was a wake-up call — DOT compliance does not automatically mean IATA compliance, even though the classification is the same.

The overlap between DOT and IATA is much greater than most people expect. The classification framework is the same — it comes from the same IAEA source. The differences are in the operational layer: what the carrier requires, what paperwork looks like, and what configurations are allowed on which aircraft.

Who Needs to Know This

This comparison is relevant to anyone who:

• Ships radioactive material by ground and is considering or required to add air as a transport mode
• Receives shipments by air and needs to understand the documentation differences
• Prepares hazmat employees for training that covers both ground and air
• Works in health physics or radiation safety and advises on shipping logistics
• Manages logistics for medical isotopes, sealed sources, or instruments that routinely ship by air

The Complete Comparison: IATA DGR vs DOT 49 CFR

This table is the core reference. Bookmark it. The left column is what you are used to from ground shipping; the right column is what changes (or stays the same) for air.

What Stays the Same: The Classification Is Identical

This is the single most important point in the entire article: the classification does not change. If your material is classified as UN2915, RADIOACTIVE MATERIAL, TYPE A PACKAGE, SPECIAL FORM under DOT 49 CFR, it is the exact same classification under IATA DGR. You do not reclassify for air.

The reason is straightforward. Both DOT and IATA derive their classification system from the same source — the IAEA Regulations for the Safe Transport of Radioactive Material (SSR-6). The A1 and A2 values in 49 CFR 173.435 are the same numbers as in IATA DGR Table 10.3.A. The UN number assignment logic, the label categories, the fissile exemptions, the definition of radioactive material — all identical.

When I train shippers who think they need to reclassify for air, I tell them this: “Your UN number does not have a transport mode. UN2915 is UN2915 whether it goes on a truck, a plane, or a boat.” That usually clicks immediately. The classification comes from the IAEA, which does not care how the material gets from A to B — it cares about what the material is, how much activity it has, and what package it is in. What changes for air is the set of rules applied after classification. I compare it to a driver's license: your identity does not change when you drive on a highway versus a local road, but the speed limit does.

What Changes: The Six Key Differences

1. Transport Index Limits Are Tighter for Passenger Aircraft

On the ground, a single package can have a TI up to 10.0. By air on a passenger aircraft, the maximum TI per package drops to 3.0. Cargo aircraft retain the 10.0 limit.

This means a YELLOW-III package with a TI of 5.0 — perfectly legal on a ground vehicle — cannot go on a passenger aircraft. It must go cargo-only. This is one of the most common reasons a shipment gets restricted to cargo aircraft.

The combined TI limit also differs: 50 on a passenger aircraft (same as a ground vehicle under non-exclusive use) but no limit on a cargo aircraft under exclusive use.

The most common mistake I see is exactly that — shippers assume the ground TI limit of 10.0 applies to all aircraft. They have a YELLOW-III package with a TI of 5.0, and they book it on a passenger flight without a second thought because 5.0 is well within the 10.0 ground limit. Then the airline rejects it because the passenger aircraft limit is 3.0. The frustrating part is that the shipment could have gone on a cargo flight without any issue. The shipper just needed to know the 3.0 threshold and book the right service. That being said, once a shipper learns the 3.0/10.0 split, they rarely forget it — it is one of those rules that sticks after you get burned once.

2. Certain Materials and Packages Are Prohibited

The IATA DGR has a list of outright prohibitions with no equivalent in DOT ground shipping (IATA DGR §10.9.3.3). See our dedicated guide on materials prohibited from air transport for the complete list. The key ones:

• Forbidden on ALL aircraft: Vented Type B(M), packages requiring external cooling, packages with operational controls, pyrophoric materials
• Forbidden on PASSENGER aircraft: Type B(M) packages, exclusive use shipments
• Special arrangement required: Any package with surface dose rate > 2 mSv/h

3. Documentation Is Different: DGD vs BOL

Ground shipments use a Bill of Lading (BOL) or shipping paper under 49 CFR 172.200. Air shipments require a Shipper's Declaration for Dangerous Goods (DGD) under IATA DGR §10.8. The DGD is a specific form with mandatory formatting requirements:

My biggest tip for first-time DGD preparation: get a blank DGD form and fill out a practice one before you have a live shipment to deal with. The form has a specific layout, and the first time you see it under time pressure is not when you want to be figuring it out. The most common formatting errors I see are using Curies instead of Becquerels, forgetting to include the proper shipping name exactly as it appears in the DGR, and not signing the declaration. Keep in mind that typewritten signatures are not accepted on a DGD — someone has to physically sign it. I also see shippers forget the two-copy requirement. One original goes to the operator, and one accompanies the shipment. Show up with one copy and you are not flying that day.

4. Units Must Be SI

This trips up US shippers more than anything else. In the United States, Curies (Ci, mCi, µCi) are the customary units for activity, and many DOT shipping papers use them. The IATA DGR requires SI units only on the DGD: Becquerels (Bq) with the appropriate SI prefix (kBq, MBq, GBq, TBq).

If you are accustomed to writing “50 mCi” on your shipping papers, you need to convert to “1.85 GBq” for the DGD. RadShip's activity guide covers unit conversions in detail.

5. Training Recurrence Is More Frequent

DOT requires recurrent hazmat training every 3 years (49 CFR 172.704). IATA requires recurrence every 2 years (DGR §1.5). If you ship by both ground and air, the IATA 2-year cycle becomes your effective training interval.

Most of the facilities I work with that ship both modes take a combined course that covers DOT 49 CFR and the IATA DGR together. It is more efficient, and the training provider can highlight the differences directly rather than making you piece it together yourself. My recommendation is to find a training program that specifically addresses the crossover points — the DGD vs the BOL, SI units vs customary, and the 3.0 TI limit for passenger aircraft. If you can only do one course, make sure it covers air. A shipper trained on IATA who also ships ground will do fine — the DGR includes everything in 49 CFR plus more. A shipper trained only on DOT who tries to ship air will run into problems.

6. State and Operator Variations

DOT 49 CFR is a single, unified US regulation. The IATA DGR, being international, includes state variations (country-specific rules) and operator variations (airline-specific restrictions) layered on top of the base requirements. A shipment that is fully DGR-compliant may still be rejected by a specific airline due to its operator variations.

For example, some carriers refuse Class 7 material entirely. Others have specific packaging or documentation requirements beyond the base DGR. You must check with your carrier before preparing the shipment.

I worked with a facility that shipped a calibration source to an overseas client. They did everything right with the DGR — DGD completed correctly, TI under 3.0, proper labels, the whole nine yards. They booked through a freight forwarder who used a connecting flight through a Middle Eastern hub. The transit country had a state variation that required additional documentation for radioactive material transiting through its airspace. The shipment got held at the hub for three days while the paperwork was sorted out. The source's calibration certificate was date-sensitive, so by the time it arrived, the client had to reschedule. The takeaway: when your route involves international connections, check state variations for every country in the routing, not just the origin and destination.

US Shippers: Which Framework Governs?

This is a common point of confusion. In the United States, the legal authority for air transport of hazardous materials is 49 CFR Part 175. However, 49 CFR 171.22 through 171.24 explicitly allow compliance with the ICAO Technical Instructions as an alternative for international air shipments.

In practice, the question is usually moot because airlines require IATA DGR compliance for acceptance regardless of what the US regulations allow. The DGR implements the ICAO Technical Instructions, so complying with the DGR satisfies both frameworks. Think of it this way:

• Legal compliance: 49 CFR Part 175 (US domestic) or ICAO TI via 49 CFR 171.22 (international)
• Practical compliance: IATA DGR (what airlines require for acceptance)
• Result: Follow the IATA DGR and you satisfy both

My recommendation is to learn the IATA DGR and use it as your primary reference for air shipments. In practice, 49 CFR Part 175 and the DGR arrive at the same place, but the DGR is what the airlines use for acceptance. I have never had a carrier ask me to show compliance with Part 175 — they want to see a properly completed DGD per the DGR. That being said, it is worth knowing that Part 175 exists and that 49 CFR 171.22 authorizes ICAO TI compliance, because that is the legal backstop for US shippers using an international standard. If you are ever audited by DOT/PHMSA, understanding both frameworks shows you know what you are doing.

How RadShip.com Helps

RadShip.com bridges the gap between ground and air shipping:

• RAMcalc — Classifies your material once, with the result valid for both ground and air. No need to reclassify.
• Regulatory Guides — Covers both DOT and IATA requirements with cross-references between the two frameworks
• LabelCalc — Label categories are the same for both modes — determine once, apply everywhere

Here's the reality: most shippers do not ship exclusively by one mode forever. At some point, ground-only shippers need to send something by air — an emergency delivery, a return shipment, an overseas transfer. When that moment comes, the last thing you want is to start the classification process over from scratch in a different system. Having one tool that gives you a classification valid for both modes means you are always prepared. You classify once, and you know your UN number, your TI, your label category, and your package type — regardless of whether the shipment goes on a truck or a plane. That saves time and eliminates the risk of transcription errors between two different workflows.

Try it free for 7 days.

Common Questions

Are A1 and A2 values different between IATA and DOT?

No. Both derive from the same IAEA source. The values in 49 CFR 173.435 and IATA DGR Table 10.3.A are identical.

Can I use DOT 49 CFR for international air shipments?

Yes, with conditions. 49 CFR 171.22–171.24 allows compliance with the ICAO Technical Instructions for international air transport. However, airlines require IATA DGR compliance for acceptance, so in practice you follow the DGR.

Do I need both DOT and IATA training?

If you ship by both modes, yes. Many shippers take combined training that covers both frameworks. The IATA 2-year recurrence cycle becomes your effective training interval since it is more frequent than DOT's 3-year cycle.

Is the DGD the same as a shipping paper?

No. The DGD is a specific IATA form with different requirements than a BOL. It must use SI units, be in English, include two signed copies, and follow the specific format in IATA DGR §10.8.

Can I use Curies on air shipping documents?

No. The DGD requires SI units (Becquerels). Curies may appear as supplementary information, but the SI value is the official entry. 1 Ci = 37 GBq.

Honestly, the transition from DOT-only to DOT-plus-IATA is not as hard as most people fear. If you already know 49 CFR Subpart I, you know about 80% of what you need for IATA. The classification is the hard part, and you already have that down. What you are adding is a handful of operational differences — the DGD form, SI units, the 3.0 TI limit for passenger aircraft, and checking operator variations. I would tell someone who is anxious about it to start with one shipment. Prepare the DGD, call the carrier, walk through the process once with full attention. After that first successful air shipment, it becomes routine. The IATA DGR looks intimidating because it is a thick manual, but Section 10 is well-organized, and once you know where to find things, it is no more complex than 49 CFR.

Summary: Your Ground-to-Air Transition Checklist

When adding air transport to your shipping capabilities, ensure:

• ☐ You understand that classification does not change — same UN number, same package type
• ☐ You know the TI limits for passenger (3.0) vs cargo (10.0) aircraft
• ☐ You have reviewed the prohibited materials list (IATA DGR §10.9.3.3)
• ☐ You can prepare a DGD with SI units (Becquerels, not Curies)
• ☐ You have IATA-specific training (recurrent every 2 years)
• ☐ You have verified your carrier accepts Class 7 material and checked operator variations
• ☐ You know when advance notification is required (>3000 A1/A2, Type B(M), special arrangement)
• ☐ You have a current copy of the IATA DGR accessible to shipping personnel

Regulatory References

DOT Requirements (Ground):

• 49 CFR Part 173, Subpart I — Class 7 radioactive material requirements
• 49 CFR 172.202 — Shipping paper description requirements
• 49 CFR 172.704 — Training requirements
• 49 CFR Part 175 — Carriage by aircraft (US domestic)
• 49 CFR 171.22 — Authorization to use ICAO TI

IATA DGR (Air Transport):

• IATA DGR §10.3 — Classification (same as DOT, IAEA-sourced)
• IATA DGR §10.8 — Documentation (DGD requirements)
• IATA DGR §10.9.3.3 — Loading limitations and prohibitions
• IATA DGR Table 10.9.B — TI and CSI limits per aircraft type
• IATA DGR §1.5 — Training requirements (2-year recurrence)
• Purchase the IATA DGR