MANAGEMENT OF NORM IN THE PETROLEUM INDUSTRY Akpojevwa Tega Naomi, october 2016 | Page 29

The activity concentration of Radon-222 in gas processing plants can be found
in table 2.5. The decay products of Radon-222 can become a hazard for the
workers and environment if they get in contact with short-lived gamma
radiation from Bismuth-214 or long-lived radiation from Lead-210 and
Polonium-210 (OGP 2008; IAEA 2003; NRC 1999).
Table 2.4: Activity concentration in gas processing plants (Jonkers et al. 1997)
Radon is a radioactive gas, which is present in varying degrees in natural gas in
oil & gas formations. In the absence of natural gas, radon dissolves in the (light)
hydrocarbon and aqueous phase. When produced with the oil and gas, radon
will usually follow the gas stream. If the natural gas is fractionated, a
disproportionately high percentage of radon can concentrate in the propane
streams and to a lesser degree in the ethane streams.
Radon-222 produces, through natural decay, several radioactive nuclides (also
known as radon progeny). Most radon progeny are short-lived, with the
exception of Lead-210 and Polonium-210, which have relatively long half-lives
of 22.6 years and 138 days respectively. Most of the radon decay products (90-
99%) are attached to ambient aerosols, airborne particulates or surfaces. This
can result in forming thin radioactive films on the inner surfaces of gas
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