The safety basics the law expects
California rentals must have working locks on entry doors and windows, working smoke alarms, and — where required — carbon monoxide alarms, along with safe stairways, railings, and exits. These features are part of keeping a home fit to live in.
State law requires a deadbolt lock on the main entry door and operable locks on windows in many rentals. Smoke alarms must be working, and carbon monoxide alarms are required in units with fuel-burning appliances, fireplaces, or an attached garage. Stairs, handrails, and walkways must be maintained so they are safe to use, and exits must not be blocked.
Missing or broken safety features can be habitability violations, and they matter in another way too: if someone is hurt because a required safety feature was missing or broken, the landlord may be responsible for that injury. If your rental is missing these basics and the landlord will not fix them, it is worth getting guidance.
This is general information about California tenant rights, not legal advice. Every situation is different.