This occurrence underscores the importance of completing a hazard analysis for each different process. Non-safety-related systems or equipment may be used for purposes other than their primary purpose so long as potential hazards are identified and engineering and administrative controls are applied to eliminate or minimize them. The filling of lecture bottles seemed to fall within the safety envelope previously established for high-pressure testing; however, the rupture of a cylinder revealed an unanticipated potential to release an overfilled gas cylinder to laboratory personnel.