Under United States federal law, possession of nitrous oxide is legal and is not subject to DEA purview. It is, however, regulated by the Food and Drug Administration under the Food Drug and Cosmetics Act. Prosecution as a Federal misdemeanor is possible under its “misbranding” clauses, punishable by up to one year in federal prison and a fine of $100,000.
Possessing or selling Nitrous Oxide for legitimate business reasons is not illegal. However, selling or using Nitrous Oxide to get high is illegal in California.
California Penal Code section 381b & 381d makes it a misdemeanor, punishable by up to six (6) months in county jail, a fine not to exceed one thousand dollars ($1,000), or by both, to possess Nitrous Oxide with the intent to inhale it and get high.