The goal of this clinical trial is to see if nitrous oxide is safe and effective to use during during vasectomies performed in a clinic/in-office setting. This trial will compare self-administered nitrous oxide versus a placebo (oxygen) during office vasectomy. The main questions it aims to answer are: * Whether self-administered low dose (20-45%) nitrous oxide (SANO) reduces intraoperative anxiety and catastrophizing during office vasectomy. * To examine whether SANO reduces intraoperative pain or alters procedure duration, the rate of adverse events, or urologists' perception of ease and patient tolerance of the procedure. Participants will be asked to complete multiple surveys pre-procedure, intra-procedure, and post-procedure.