Operational since 1967. Yarnell Security Systems is a local central station. Installation. And monitoring Company. Located in lancaster. PA. . It provides sales. Service. Installation and monitoring of burglar alarms. Fire alarms. Panic and emergency buttons among others. In residences and commercial buildings. The Company is LANCASTER'S oldest locally owned central station. Yarnell Security Systems is the number ONE Reader's choice awards winner. It is a member of lancaster chamber of commerce. Pennsylvania burglar and fire alarm association (PBFAA) and NFPA. The Company is underwriters laboratories (UL) and national institute for certification in engineering technologies (NICET) certified.