TABLE 2.

Lung cancer mortality in British radiologists from 1897–1979^*

		SMR (COMPARED TO UK MALE NON-RADIOLOGIST PHYSICIANS)
Years Joined Radiological Societies	Tolerance or Exposure Limits	All Cancers	Lung Cancer
1897–1920	> 1 Sv yr1	1.75	2.46
1921–1935	< 1 Sv yr1	1.24	1.06
1936–1954	2 mSv day−1 or 500 mSv yr−1	1.12	0.74
1955–1979	50 mSv yr−1	0.71	0

^*Berrington el al. 2001