28 30 00 Electronic Detection and Alarm 28 20 00 Electronic Surveillance 28 13 00 Access Control 28 10 00 Electronic Access Control and Intrusion Detection / Surveillance 27 41 00 Audio-Video Systems 27 21 00 Data Communications Network Equipment 27 20 00 Data Communications 27 13 00 Communications Backbone Cabling 27 10 00 Structured Cabling 27 04 00 Audio-Video Systems

25 10 00 Integrated Automation Network Equipment 26 20 00 Low-Voltage Electrical Transmission 27 10 00 Structured Cabling 27 13 00 Communications Backbone Cabling 27 21 00 Data Communications Network Equipment 28 10 00 Electronic Access Control and Intrusion Detection / Surveillance