Under GB 11806 and JT/T 617.5, what are the maximum allowable radiation dose rate limits on the external surface of a road transport vehicle and in the driver's cab, respectively, during routine transport of Class 7 Radioactive Material?

1. External surface maximum 2 mSv/h; Driver's cab maximum 0.02 mSv/h (20 μSv/h)
2. External surface maximum 100 mSv/h; Driver's cab maximum 50 mSv/h
3. External surface maximum 0.001 mSv/h; Driver's cab maximum 0.0001 mSv/h
4. There are no statutory limits as long as the driver wears lead sunglasses