- Emergency alarms (6)
- Burglar alarm apparatus, electric (1)
- Fire alarm apparatus, electric (1)
- Fire detection systems, electric (1)
- Sirens, electric: vehicle, marine, industrial, and air raid (1)
- Smoke detectors (1)
- Transportation signaling devices (5)
- Pedestrian traffic control equipment (3)
- Signaling apparatus, electric (1)
- Traffic signals, electric (3)
- Intercommunication systems, electric (8)
- Visual communication systems (2)
