MANAGEMENT OF NORM IN THE PETROLEUM INDUSTRY Akpojevwa Tega Naomi, october 2016 | Page 38

As clinical symptoms have not been verified at doses lower than 100 mSv, there
is no universal medical surveillance programme for expected low level doses
contracted by NORM work activities. Once NORM management practices are
implemented, only in rare cases oil and gas industry workers may receive doses
exceeding 1 mSv/year. For appropriate control generally a pre-defined action
level is set in a NORM management system, so that dose can be kept as low as
reasonably practical and the root cause for exceeding the action level may be
investigated.
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