BADGE-TYPE PASSIVE SAMPLER FOR MONITORING AMBIENT AMMONIA CONCENTRATIONS

A passive ''badge-type'' sampling device for the determination of gaseous ammonia was developed. The collection substrate is phosphoric acid. The sampler can be used for outdoor and indoor sampling of ammonia in the concentration range from 0.05 mu g/m(3) to 10 mg/m(3). The performance was tested in the laboratory and in the field against an annualar denuder, a filter pack and an impinger technique. The intercalibration showed that the passive sampler compares very well with active samplers (r(2) = 0.99; k = 1.05). The average reproducibility of the sampler was 8%. Hence the badge sampler is well suited for the determination of ammonia in a wide range of concentrations and particularly for application under rural background conditions. The sampling rate of the device was calculated according to a simple multi-layer model.