Summary of U.S. DOT Radiation Limits

MEASURING POINT RATE LIMIT
Exclusive Use Vehicles
Two meters (6.6′) from sides-enclosed trailer .1 mSv/hr (10 mrem/hr)
Two meters (6.6′) from vertical plane of trailer edge (flatbed) .1 mSv/hr (10 mrem/hr)
At contact on surface of side and top-enclosed trailer 2 mSv/hr (200 mrem/hr)
At contact on any surface of load (flatbed) 2 mSv/hr (200 mrem/hr)
On vertical plane of trailer edge (flatbed) 2 mSv/hr (200 mrem/hr)
Surface of bottom of trailer 2 mSv/hr (200 mrem/hr)
Package surface (enclosed trailer only) 10 mSv/hr (1000 mrem/hr)
Occupied area of vehicle .02 mSv/hr (2 mrem/hr)
Non-Exclusive Use Vehicles
One meter (3.3′) from any surface of package .1 mSv/hr (10 mrem/hr)
Package surface 2 mSv/hr (200 mrem/hr)