1 terabecquerel (TBq) = 1 × 1012 Bq. For the period 1952 to 1976, discharges have mainly been estimated and are considered to be relatively uncertain.
Are we moving in the right direction?
In the mid-1990s, the technetium-99 discharges from Sellafield to the Irish Sea increased, growing from a few TBq per year to a peak of 190 TBq in 1995. The technetium-99 discharges remained relatively high until 2003-2004, when Sellafield implemented new technology to remove the technetium-99.
During the last few years, the discharges have been below 10 TBq per year, and the discharge in 2010 was 1.4 TBq.
Published by the Norwegian Radiation Protection Authority, 20.11.2011, 19:41.