Figure 6.1: The percentage of measured 24-hour average PM₁₀ concentrations for Whangarei within air quality categories (left) and measured concentrations (right)

Text description of figure

There are two charts showing PM₁₀ 24-hour concentrations for Whangarei.

The first chart shows concentrations of PM₁₀ measured against air quality categories. About 25 per cent of concentrations were in the 'good' category, 50 per cent were 'acceptable', about 20 per cent were 'alert', and about 5 per cent were above the guideline.

The second chart shows measurements of monthly PM₁₀ concentrations against the Ministry for the Environment guideline between October 2000 and July 2001. Measurements were generally low, except for a spike in January 2001, which went well over the guideline (to 70µg m^-3). Concentrations were higher on average during the autumn months.