Certs are interesting . . . Essentially, they give vendors "permission" to sell HPR motors to certified rocketeers, thus releasing them from culpability, so they can claim that NAR or TRIPOLI told them that it was OK to sell HPR motors to someone . . . Certs also function as a "leash" on rocketeers, to both limit what motors they have access to and to force them to be members of either NAR or TRIPOLI, or have no access to HPR motors.

Regulation also does the same thing, but at a state or national level, regulating manufacturers, vendors, and consumers.

Dave F.