40 CFR §1068.27

1. (a)As described in the standard-setting part, we may perform testing on your engines/equipment before we issue a certificate of conformity. This is generally known as confirmatory testing.
2. (b)If we request it, you must make a reasonable number of production-line engines or pieces of production-line equipment available for a reasonable time so we can test or inspect them for compliance with the requirements of this chapter.
3. (c)If your emission-data engine/equipment or production engine/equipment requires special components for proper testing, you must promptly provide any such components to us if we ask for them.