AIRBORNE CONTAMINANT INDICATOR

摘要

An indicator system (18) provides a visual indication of the cumulative leve l of an airborne contaminant. The indicator is a transparent sheath (20) with support medium having an acidic surface and treated with a color pH indicato r (20). As a basic contaminant is adsorbed by the medium, the medium color changes. As additional contaminant is adsorbed, the color front progresses t he length of the indicator. The indicator system may be used with an adsorptive filter system to predict the life of adsorption bed assemblies. A sample flo w is taken upstream of the adsorption beds and is passed through the indicator . Preferably, the flow rate is calibrated so that the rate of the color change in the indicator is proportional to the rate of depletion of the adsorption bed. By monitoring the indicator, an accurate prediction of adsorption bed life may be made.