IMDG Class 7 covers any material containing radionuclides where both the activity concentration and total activity exceed specified exemption values. Unlike other DG classes, Class 7 is not divided into divisions or packing groups — instead, the level of restriction is determined by the radionuclide, activity level, packaging type, and transport index. Class 7 is by far the most challenging DG class to ship from China, with extremely limited carrier acceptance, extensive regulatory approvals, and the longest lead times of any DG category.
How Class 7 Is Regulated (No Packing Groups)
Class 7 does not use the standard Packing Group (PG I/II/III) system. Instead, shipments are governed by:
- A1 and A2 values: Each radionuclide has maximum activity limits for Type A packaging. A1 applies to "special form" (non-dispersible, certified solid) radioactive material. A2 applies to all other forms. Exceeding A1/A2 means Type B packaging is required.
- Transport Index (TI): Radiation level at 1 meter from the package surface, in mrem/h. Determines stowage distance requirements.
- Excepted packages: Very low-activity material with surface radiation <0.005 mSv/h. Ships as non-DG with simplified documentation.
- Type A packaging: For moderate activity (within A1/A2 limits). Must survive normal transport conditions.
- Type B packaging: For high activity (exceeding A1/A2). Must survive severe accident conditions (9m drop, 800°C fire, water immersion).
Common Class 7 Products Exported from China
- Medical radioisotopes: Iodine-131 (I-131, UN2915) — thyroid cancer and hyperthyroidism treatment, half-life 8 days. Technetium-99m (Tc-99m, UN2915) generators — the most widely used medical imaging isotope globally, half-life 6 hours. Lutetium-177 (Lu-177, UN2916) — targeted cancer therapy, half-life 6.6 days. These are almost always air freight shipments due to short half-lives.
- Industrial radiography sources: Iridium-192 (UN2916) — non-destructive testing of welds and pipelines, half-life 74 days. Cobalt-60 (UN2916) — industrial sterilization and radiotherapy, half-life 5.3 years. Ships in Type B casks by sea. Requires CAEA authorization for export.
- Industrial gauges and instruments: Density gauges, level gauges, and thickness gauges containing sealed sources (Cs-137, Am-241, Kr-85). Typically low-activity (Category I-WHITE). UN2911 for instruments, UN3332 for articles.
- Smoke detectors (americium-241): UN2911 for consumer products containing Am-241. Ships as excepted packages if activity is very low. Common in fire safety equipment exports from China.
- NORM-contaminated equipment: Naturally Occurring Radioactive Material from oil/gas pipes, mining equipment. UN2912 (LSA-I) or UN2913 (LSA-II). Requires decontamination certificate or activity measurement report. Exported as waste or for decontamination/refurbishment.
- Uranium ore concentrates (yellowcake): UN2912 (LSA-I). Heavily controlled export from China with CAEA and international safeguards notification. Not a routine commercial shipment.
Packaging Requirements
Class 7 has the most complex packaging system in the IMDG Code:
- Excepted package: Simple packaging with radiation warning on inner article. External package shows no radioactive marking. Surface dose rate ≤0.005 mSv/h. No UN number on outer package. Suitable for smoke detectors and check sources.
- Industrial package (Type IP-1, IP-2, IP-3): For LSA (Low Specific Activity) and SCO (Surface Contaminated Object) materials. IP-1 is basic industrial packaging. IP-2/IP-3 require more robust construction. Used for NORM waste and contaminated equipment.
- Type A package: Must prevent loss/dispersal of radioactive contents and retain shielding integrity under normal transport conditions (water spray, free drop, stacking, penetration tests). Certified by national competent authority (CAEA in China). Maximum activity limited by A1/A2.
- Type B(U) / Type B(M) package: Must withstand severe accident conditions (9m drop, 1m punch drop, 800°C fire for 30 min, 15m water immersion for 8 hours). Unilateral approval by country of origin for B(U); multilateral approval for B(M). Used for high-activity sources, spent fuel casks.
Radiation Labels and Category System
| Label Category | Color | Surface Dose Rate | Dose Rate at 1m | Transport Index (TI) |
|---|---|---|---|---|
| Category I | White | ≤0.005 mSv/h | N/A (background) | 0 |
| Category II | Yellow | ≤0.5 mSv/h | ≤0.01 mSv/h | 0-1 |
| Category III | Yellow | ≤2 mSv/h | ≤0.1 mSv/h | 1-10 |
Carrier Acceptance (Highly Restricted)
| Carrier | Excepted Package | Type A (LSA/SCO) | Type B | Air Freight |
|---|---|---|---|---|
| MSK | Accepted | Case-by-case | Not accepted | N/A (sea only) |
| HPL | Accepted | Not accepted | Not accepted | N/A |
| MSC | Accepted | Case-by-case | Not accepted | N/A |
| COSCO | Accepted | Case-by-case | Limited | N/A |
| HMM | Accepted | Not accepted | Not accepted | N/A |
| OOCL | Accepted | Not accepted | Not accepted | N/A |
| EMC | Accepted | Not accepted | Not accepted | N/A |
| YML | Accepted | Not accepted | Not accepted | N/A |
| CMA CGM | Accepted | Case-by-case | Not accepted | N/A |
For air freight of medical isotopes: Dedicated cargo airlines and IATA-certified carriers with radiation-trained crews handle these shipments. Passenger airlines generally prohibit Class 7 on passenger flights. Medical isotopes are the primary exception — time-critical shipments via air on cargo aircraft with pre-approval.
Special China Export Controls for Class 7
China imposes additional layers of regulation on Class 7 exports beyond the IMDG Code:
- CAEA Export License: The China Atomic Energy Authority (CAEA, 中国原子能机构) must issue a Nuclear Material / Radioactive Material Export License for most Class 7 shipments. This is separate from standard customs export procedures.
- Packaging certification by CAEA: Type A and Type B packages must be certified by CAEA or a CAEA-recognized body. Foreign packaging certifications are not automatically accepted.
- Shipper qualification: The exporter must be a CAEA-registered entity licensed to handle radioactive materials. Chinese isotope producers (e.g., CNNC subsidiaries) hold these licenses.
- Destination import license: The consignee must provide a valid import license or authorization from their national nuclear regulatory authority before the shipment loads in China.
- Dual-use controls: Some radioisotopes and equipment may be subject to additional dual-use export controls under MOFCOM regulations if they could be diverted to nuclear weapons programs.
Documentation Checklist
- CAEA Radioactive Material Export License
- CAEA Package Design Approval Certificate (Type A or B)
- Shipper's Declaration for Dangerous Goods (IATA format)
- Radiation survey report (surface dose rate and 1m dose rate measurements)
- Transport Index (TI) calculation sheet
- MSDS (where applicable) with radionuclide data
- Destination country import license / authorization
- DG Packaging Certificate (危包证)
- Maritime DG Declaration
- Port Filing Approval
- Emergency response information (24-hour contact)
- Commercial Invoice, Packing List, B/L
- Carrier DG Booking Confirmation (with radiation acceptance letter)
Frequently Asked Questions
How long does it take to get CAEA export approval for a Class 7 shipment?
For routine medical or industrial isotopes with established export history, CAEA approval typically takes 2-4 weeks. For new applications, first-time exporters, or unusual isotopes, allow 4-8 weeks. For Type B packages or spent fuel, the approval process can take 3-6 months and involves multilateral regulatory coordination. The CAEA approval timeline is often the critical path for Class 7 shipments and must be factored into project planning before cargo is even packaged.
Can smoke detectors be shipped as non-DG from China?
Yes, most consumer smoke detectors containing americium-241 (typically <40 kBq per unit) ship as "excepted packages" under UN2911. They require no external radioactive marking or DG documentation. However, this only applies to individually packaged consumer products. Bulk shipments of bare Am-241 sources or industrial quantities may exceed excepted package limits and require full Class 7 compliance. Always verify the total activity per package against the excepted package limits in the IMDG Code Table 2.7.2.4.1.2.
Can medical isotopes be air freighted from China?
Yes, medical radioisotopes are regularly air freighted from China, predominantly through Beijing Capital Airport (PEK) and Shanghai Pudong Airport (PVG). Key requirements: CAEA export authorization, IATA DGR compliance, Type A certified packaging, pre-booking with an IATA-certified carrier (typically Air China Cargo, China Cargo Airlines, or international carriers with isotope acceptance), 24/7 shipment monitoring, and pre-arranged customs clearance at destination. Due to short half-lives (hours to days), these shipments operate on tightly scheduled logistics chains with airport radiation monitoring and dedicated handling teams. Lead time for establishing a new isotope export route is typically 3-6 months.
What is a Transport Index (TI) and why does it matter?
The Transport Index is the maximum radiation dose rate at 1 meter from the package surface, expressed in mrem/h (or µSv/h divided by 10). It determines: (1) which Category label (I/II/III) the package carries, (2) minimum separation distance from passengers, crew, and undeveloped film during transport, (3) total TI limits per container (typically max 50) and per vessel (typically max 200), and (4) whether the package can be transported in a closed vehicle or needs special stowage. For Class 7 shippers, accurate TI calculation is essential — underestimating TI is a serious regulatory violation.