G
PHYSICS
G08
SIGNALLING
G08B
SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
17/00
Fire alarms; Alarms responsive to explosion
G08B17/10
Actuation by presence of smoke or gases; , e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means
G08B17/11
using an ionisation chamber for detecting smoke or gas
G08B17/113
Constructional details