Hastings has had its first exceedance of the air quality standards this winter.

On Sunday, the average level of PM10 measured at the St John's air quality monitor site over a 24 hour period was 55mcg/m3

It was almost the second exceedance, as Saturday had a close call when the Hastings monitor measured 49mcg/m3.

Smoky air was observed over much of Napier and Hastings during the evenings over the weekend.


"We had expected an exceedance over the long weekend given the forecast for clear, still weather across the region, and chilly temperatures compared to the warm days we had all through May," says HBRC's air quality scientist Dr Kathleen Kozyniak.

Queen's Birthday Weekend last year was also when the first exceedance in Hastings occurred.

There were similar weather conditions resulting in a similar average level of PM10 of 54mcg/m3 over 24 hours.

The air pollution problem in Hastings and Napier is caused by smoky air being trapped close to the ground when inversion layers form in the atmosphere over the plains during cold, low wind conditions.

The small particles in smoke - or PM10 - is a health issue inside and outside homes, especially for people with respiratory problems.

Hawke's Bay Regional Council has been working with the community to improve the air quality around our cities in winter. HBRC has a two initiatives to reach the required NES limits, including financial assistance to replace out-dated burners, and an accreditation process for wood burners.

The use of open fires has been banned in Napier and Hastings since early 2012.

Since January this year, wood burners installed before 2005 are illegal to use as these were not manufactured to new standards introduced that year to ensure fuel burns more cleanly with less smoke.

"People having been making good use of HBRC Heatsmart grants and low interest loans to replace older burners, so we should see fewer smoky days," says Mark Heaney, HBRC's HeatSmart manager.

"We also recommend people only use dry, untreated wood in their burners by either storing the wood properly for at least six months or buying it from an HBRC approved wood merchant.

"They get more heat for their dollar with dry wood."

National Environmental Standard - Air Quality

The National Environmental Standard (NES) for air quality sets an acceptable limit for fine smoke particles in the air (measured as PM10) of 50mcg of PM10 per cubic metre averaged over 24 hours.

From September 2016 the NES will require this limit to be exceeded only once a year in Napier and no more than three occasions in Hastings, before reducing to only one exceedance a year by September 2020.