The latest CPCB limits for environmental pollutants like SO2, NO2, NH3, Cl2, O3 etc. The threshold limit value (TLV) for all these pollutants are in the ppb level. Hence to monitor these pollutants at such low concentrations conforming to CPCB norms, it requires very sensitive detection instruments. It is also necessary to monitor the environment to find the TWA (Time weighted average) concentrations of these pollutants on 8 hour to 24 hour basis.
Uniphos Envirotrack which UEPL developed is a microprocessor based non dispersive spectrophotometer tailor, which is made to analyze all the above mentioned five pollutants at parts per billion levels. The instrument is light weight and available at moderately priced.