Figure 3.7: Percentage of measured one-hour and 24-hour average NO₂ concentrations within air quality categories at Packe Street and Coles Place, Christchurch

Text description of figure

There are four charts showing one-hour and 24-hour concentrations of NO₂ in Christchurch. The first two charts show concentrations measured at Packe Street, Christchurch from 1992 to 2001. Concentrations were mostly “Excellent” and “Good”, and improved from 1992 to 1998, while dipping slightly in 2001. The second two charts show concentrations measured at Coles Place, Christchurch from 1999 to 2002. Low values were consistently measured for the 24-hour concentrations, while one-hour concentrations rose slightly over the period.