The NAR, founded in 1957, initially advocated for model rocketry. Over the years, the hobby expanded, leading to certification for high power rocketry, allowing enthusiasts to use advanced rocket motors and exceed traditional boundaries. Certification involves three progressive levels, level 1 2 and 3. The procedures are listed below and are obtained from the official NAR website 

https://www.nar.org/high-power-rocketry-info/level-1-hpr-certification-procedures/

1. The Level 1 High Power Certification Candidate must build the rocket that they wish to use for their certification attempt. The model may be either scratch built or a kit and the rocket must be constructed in such a manner that it will perform safely under the additional stress of an HPR motor. Teams attempting to certify cannot use the same rocket, but rather are required to each build their own model. In addition, the member must use an active recovery system for their certification attempt, which usually includes parachute recovery; details of these recovery methods are described in the Definition of Active Recovery.

2. The Level 1 High Power Certification Candidate must demonstrate their ability to build and fly a rocket containing at least one H or I impulse class motor. Cluster or staged models used for certification may not contain over 640.00 Newton seconds total impulse. In the case of a cluster or staged model, at least one of the individual motors must be an H or I impulse motor. Combinations of smaller impulse motors that add up to meet the impulse requirements do not qualify as the model does not contain at least one H or I impulse motor. Single use, reloadable, or hybrid technology motors are permitted. The Level 1 High Power Certification Candidate must assemble the reloadable motor, if used, in the presence of a Certification Team member.

3. The Level 1 High Power Certification Candidate must complete the Applicant Information portion of a NAR Level 1 High Power Certification Application prior to the certification flight attempt.

4. The model will be subjected to a safety inspection prior to flight. A High Power Certification Checklist is located on the back of the NAR Level 1 High Power Certification Application. The Certification Team will ask the Level 1 High Power Certification Candidate the checklist questions and mark the boxes as appropriate. Also during the safety inspection, the Level 1 High Power Certification Candidate will be expected to provide oral answers to technical questions related to the safety and construction of their model. The questions may include (but not limited to) identification of the model’s center of gravity and center of pressure, methods used to determine model stability, and interpretation of the rocket motor’s designation. Once satisfied, the Certification Team will fill out/check the appropriate blocks under the HPR Level 1 Checklist prior to flight.

5. The Level 1 High Power Certification Candidate will fly their model. The flight must be witnessed directly by the Certification Team. Stability, deployment of the recovery system, and safe recovery will be considered when evaluating safety of the flight. Models experiencing a catastrophic failure of the airframe, rocket motor, and/or recovery system (e.g., shock cord separation) will not be considered as having a safe flight.

6. The model must be returned to the Certification Team directly after flight for inspection to verify engine retention and for evidence of any flight-induced damage. The Certification Team will check the appropriate blocks in the HPR Level 1 Checklist indicating that a safe flight was made and that the post-flight inspection was satisfactory. In general, the guideline for acceptable flight damage is that the model could be flown again without repair. It is left to the judgment of the Certification Team to differentiate between flight damage and “normal” maintenance to assure reliability (e.g., shock cord replacement to prevent future flight problems). “Zippering” of the body tube is another area of flight damage left to Certification Teams judgment for acceptability.