Post Alarm Systems | Post Alarm - Shields up. Since 1956.

Post Alarm is one of the oldest, largest and most respected providers of business and home security in Los Angeles and Orange County. We provide home security and business /commercial security, alarm systems, medical alert, cctv, access control, fire alarm, video surveillance, store alarms and more.Post Alarm is one of the oldest, largest and most respected providers of business and home security in Los Angeles and Orange County. We provide home security and business /commercial security, alarm systems, medical alert, cctv, access control, fire alarm, video surveillance, store alarms and more.