Timaru is failing at keeping its high air pollution days down to a minimum with the tally for the year to date being 10.
Environment Canterbury (ECan) reports Timaru had a PM10 concentration of 53 on Monday. By this time last year, Timaru had experienced 12 days where the reading was more than the health guideline of 50.
In a bid to keep high pollution days to a minimum ECan has put in place a policy of smokefree woodburners with no visible smoke.
The aim is to reduce the number of pollution days to one by next year.
The three main sources of PM10 are home heating, industry and vehicles, from the combustion of fuels such as wood, coal, petrol and diesel.
On a typical winter day in Timaru, an estimated 88 per cent of emissions come from home heating and in Washdyke 7 per cent.