Subtronics [india] has innovated a specific gas detection system for hydrogen/co gas only. It is useful when there is a mixture of gases/fumes/vapours present in their vicinity such as lpg, toluene, ammonia, hexane, alcohol vapours, etc. In such cases it gives alarm only for hydrogen/co. A three status low/medium/high gas monitor with analogue meter attachments reads three coloured zone-dial, e.G., green, [0-1%], yellow [1-2%] and red [2-2.5%] along with three coloured leds. It operates on 230v ac or 6v dc only, thus a better safety than 12v systems. It has selectable slide switch for audio/visual built-in solid-state buzzer. Any one level can be selected with users choice with green [low], yellow [medium], red [high] led indicators for three status of gas with "reset" push switch monitors concentration of hydrogen specifically in the presence of various organic/inorganic solvent vapours. It has facility to function five gas detectors [flameproof] remotely [250 mtr] with independent alarm led-latching. A 6v battery back-up, remote alarm potential free no/nc contact, recorder output are the speciality. A timer [1-1/2 min] avoids false-alarm in case of mains failure; thus visual indication of rise in concentration of hydrogen/co without audio alarm is possible.
