CFR /  Title 48  /  Part 9  /  9.303 Use.

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.