Door locks are a common part of security measures, and many states have laws that regulate the types of locks allowed on doors and how door locks may be used. These laws pertain to residential, commercial, and public buildings, and they commonly specify standards for padlocks, keyed locks, and combination locks. In addition, some jurisdictions place restrictions on the types of locks that may be used on doors in public buildings, such as those in schools, hospitals, and government buildings. The regulations also often include restrictions on who may access doors and when access is allowed. Knowing the legal guidelines regarding door locks can help ensure compliance with applicable laws.