Any quantity of packages bearing the RADIOACTIVE YELLOW III label (LSA-III).
Some radioactive materials in "exclusive use" with low specific activity radioactive materials will not bear the label, however, the RADIOACTIVE placard is required.
The absence of any hazard class or division or a blank space in the table indicates that no restrictions apply.
X: These materials may not be loaded, transported, or stored together in the same transport vehicle or storage facility during the course of transportation.
O: Indicates that these materials may not be loaded, transported or stored together in the same transport vehicle or storage facility during the course of transportation, unless separated in a manner that, in the event of leakage from packages under conditions normally incident to transportation, commingling of hazardous materials would not occur.
B: Radioactive I and II are not required to be placarded, and does not have segregation requirements. Radioactive III must be placarded in any quantity.
I - Extremely low radiation levels: 0.5 millirems (0.0050 mSv) per hour.
II - Low radiation levels: >0.5–50 millirems (0.0050–0.5000 mSv) per hour, on surface. 1.0 millirem (0.010 mSv) maximum at 3.3 feet (1 m).
III - Higher radiation levels: >50–200 millirems (0.50–2.00 mSv), on surface. 10 millirems (0.10 mSv) maximum at 3.3 feet (1 m).[1]
Source: United States Code of Federal Regulations, Title 49 CFR §177.848 - Segregation of hazardous materials.[2]