(1) For paragraph 21.420(1)(a), the applicant must carry out all inspections and tests necessary to show that the design complies with the applicable airworthiness standards for the design.
(2) Before testing a prototype of a modification or repair, the applicant must:
(a) establish the following for the prototype:
(i) that the materials and processes used to produce the prototype conform to the specifications for the design;
(ii) that all aeronautical products used in the prototype conform to the drawings in the design;
(iii) that the manufacturing processes, construction and assembly of the prototype conform to the manufacturing processes, construction and assembly specified in the design; and
(b) ensure that the accuracy of the equipment to be used for the test has been verified by a means that is traceable to:
(i) a standard recommended by the manufacturer of the equipment; or
(ii) a nationally or internationally recognised standard.
Example: For subparagraph (b)(ii), of a standard that is nationally recognised
A standard maintained by the National Measurement Institute--see
http://www.measurement.gov.au.