AGSS flow indicator

HTM 02-01 lists the AGSS plant indications as green 'mains on', green 'airflow normal', yellow 'duty pump failed' (plant fault) and red 'system failed' (plant emergency), and says the indicator panels should be installed in operating rooms. For dental anaesthetic gas scavenging units, the fan unit should produce a flow rate of no less than 80 L/min and should have a flow switch and a flow indicator to show that the system is running at a specific flow rate.

HTM 02-01 notes that AGSS flow rates directly affect the induced flow on the patient breathing system and should be set up and maintained correctly. Part B adds that AGSS maintenance is undertaken quarterly, with annual recommissioning: the tasks include confirming operation of the 'mains on' and 'running/normal' indicators, checking that a 'system failure' alarm is given when the feed pipe to a low-flow detector, where fitted, is momentarily disconnected, and taking individual flow measurements at all terminal units at both high and low settings. In the Ultra Controlo ULTRASEG, terminal units incorporate an adjustable orifice.