Testing and approval may be appropriate when—
(a) The contractor has not previously furnished the product to the Government;
(b) The contractor previously furnished the product to the Government, but—
(1) There have been subsequent changes in processes or specifications;
(2) Production has been discontinued for an extended period of time; or
(3) The product acquired under a previous contract developed a problem during its life.
(c) The product is described by a performance specification; or
(d) It is essential to have an approved first article to serve as a manufacturing standard.