Code of Federal Regulations Title 40. Protection of Environment § 40.61.91 Definitions

(a) Effective dose equivalent means the sum of the products of absorbed dose and appropriate factors to account for differences in biological effectiveness due to the quality of radiation and its distribution in the body of reference man. The unit of the effective dose equivalent is the rem. For purposes of this subpart, doses caused by radon–222 and its respective decay products formed after the radon is released from the facility are not included. The method for calculating effective dose equivalent and the definition of reference man are outlined in the International Commission on Radiological Protection's Publication No. 26.

(b) Facility means all buildings, structures and operations on one contiguous site.

(c) Radionuclide means a type of atom which spontaneously undergoes radioactive decay.

(d) Residence means any home, house, apartment building, or other place of dwelling which is occupied during any portion of the relevant year.