This alternative standard was approved on May 24, 1999 and was made retroactive to April 28, 1999. It has no time limit. It applies to facilities that do not conduct mammography every week. Rather, they may conduct mammography during some, but not all, weeks in a given month.
The final regulation and its alternative standard are stated below:
21 CFR 900.12(e)(2) states that:
(2) Weekly Quality Control Tests. Facilities with screen-film systems shall perform an image quality evaluation test, using a FDA-approved phantom, at least weekly.
The approved alternative standard is:
(2) Weekly Quality Control Tests. Facilities with screen-film systems shall perform an image quality evaluation test, using an FDA-approved phantom, in each week that clinical mammography examinations are performed, prior to the performance of such examinations.
The alternative standard requires that if the number of weeks per month in which clinical mammography is performed increases or decreases, the frequency of the performance of the phantom image quality test must automatically undergo a corresponding increase or decrease.