| Material | Specific Activity | A2 Quantity | ||
|---|---|---|---|---|
| natural uranium | 26 Bq/mg | 0.7 Ci per ton (Metric) | Unlimited | |
| Some other isotopes of interest: | ||||
| americium 241 | 0.13 TBq/g | 3.4 Ci/g | 0.0054 Ci | 1.6 mg |
| iodine 131 | 4.6 TBq/mg | 120 Ci/mg | 13.5 Ci | 11 mg |
| thallium 201 | 7.9 TBq/mg | 210 Ci/mg | 270 Ci | 1.3 mg |
| cobalt 60 | 42 TBq/g | 1.1 Ci/mg | 10.8 Ci | 10 mg |
| carbon 14 in natural air | 0.04 Bq/liter 0.03 Bq/g | 1 pCi/liter | 54 Ci (2 TBq) | 50 km^3 Ci |
Explanations:
The A2 value for natural uranium is listed as "unlimited" so that any quantity of natural uranium is zero A2.
For I-131 0.11 mg constitutes one A2. This means a single shipment of more than 0.11 mg of I-131 requires a Type-B packaging, unless the I-131 is encapsulated in a verified "special form" in which case the A1 value, which is 6 times higher, applies; and then up to 0.66 mg can be shipped without using Type-B packaging.
For thallium 201 an A2 is 1.3 mg and the A1 is the same as the A2.
For americium 241 the A2 value is 0.0054 Ci but the A1 value is 54 Ci.
For the air example the Type A quantity is computed as about 50 cubic kilometers of air; however, the activity (0.03 Bq/g) is 2000 times less than the definition of radioactive so the Type A quantity is meaningless.
Radioactive material quantities are generally referred to in curie units, however the gram or mg equivalents are presented here to provide some "real world" feel for the quantities of material that are involved.