Here's what I got from the radiation page on our website. Mine is at 1251.
Radiation Dose Standards

The deep external whole body exposure is presented in millirem (mrem), the dose equivalent unit for ionizing radiation exposure. Internationally the Sievert (Sv) is used (1mSv = 100 mrem). National and international radiation protection agencies and standards organization have established 5,000 mrem per year as the maximum permissible dose to the whole body, blood forming organs or gonads for an occupationally exposed radiation worker. (15,000 mrem is the maximum permissible annual dose to the lens of the eye, and 50,000 mrem is the maximum permissible annual dose to the extremities and skin.)

The International Atomic Energy Agency has recommended for occupational exposures arising from transport activities, where it is assessed that the effective dose is

most unlikely to exceed 100 mrem in a year, neither special work pattern nor detailed monitoring nor dose assessment programs nor individual record keeping shall be required;
likely to be between 100 mrem and 600 mrem in a year, a dose assessment program by work place monitoring or individual monitor shall be conducted;
likely to exceed 600 mrem in a year individual monitoring be conducted.
The Health Physics Society, and international radiation protection organization, as published a position paper which states:

In accordance with current knowledge of radiation health risks, the Health Physics Society recommends against quantitative estimation of health risks below an individual dose of 5,000 mrem in one year or a lifetime dose of 10,000 mrem in addition to background radiation. Risk estimation in this dose range should be strictly qualitative accentuating a range of hypothetical health outcomes with an emphasis on the likely possibility of zero adverse health effects. The current philosophy of radiation protection is based on the assumption that any radiation dose, no matter how small, may result in human health effects, such as cancer and hereditary genetic damage. There is substantial and convincing scientific evidence for health risks at high dose. Below 10,000 mrem (which includes occupational and environmental exposures), risks of health effects are either too small to be observed or are non-existent.