40 CFR 192.41 - Provisions.
(a) Provisions applicable to the element uranium shall also apply to the element thorium;
(b) Provisions applicable to radon-222 shall also apply to radon-220; and
(c) Provisions applicable to radium-226 shall also apply to radium-228.
(d) Operations covered under § 192.32(a) shall be conducted in such a manner as to provide reasonable assurance that the annual dose equivalent does not exceed 25 millirems to the whole body, 75 millirems to the thyroid, and 25 millirems to any other organ of any member of the public as a result of exposures to the planned discharge of radioactive materials, radon-220 and its daughters excepted, to the general environment.
(e) The provisions of § 192.32(a) (3) and (4) do not apply to the management of thorium byproduct material.