Spike in levels of particulate matter monitored in some areas of the country blamed on cold weather and low winds by Department of Environment in Northern Ireland, writes Michael Holder
Air pollution reached high and moderate levels in a number of areas in Northern Ireland last week, according to the countryâ€™s Department of the Environment (DoE).
The department reported a spike in monitored levels of particulate matter on Tuesday 11 DecemberÂ in Armagh, Strabane and Newry.
This was due to a combination of cold temperatures and low wind, which is fairly common in the winter months and can result in an increase in monitored particulate levels, according to the DoE.
Monitored particulate levels lowered again on Wednesday, but the DoE believes the spike on Tuesday may have been due to many households in the affected areas using extra heating, or in some cases burning coal, in order to keep warm.
High levels of particulate matter can worsen the symptoms of lung or heart disease, and an update was published on the DoE website about the spike in levels for residents in the affected areas with respiratory, heart or similar health problems.
Air pollution levels in the UK, including particulate matter, are monitored using the index approved by the Committee on Medical Effects of Air Pollution Episodes (COMEAP). This system uses a 1-10 index, with monitored levels of air pollution from 1-3 considered â€˜lowâ€™, 4-6 â€˜moderateâ€™, 7-9 â€˜highâ€™ and pollution levels reaching 10 considered â€˜very highâ€™.
Levels of particulate matter monitored in Armagh, Strabane and Newry reached as high as 7 on the DoEâ€™s index on Tuesday, and were therefore considered to be â€˜highâ€™. Moderate levels between 4 and 6 were also measured on the same day in Ballymena, Belfast, Lisburn and Derry/Londonderry areas.
Particulate levels are monitored on the index as a mean reading from the last 24 hours, with the latest figures are updated on the DoEâ€™s Northern Ireland Air website.
Dan Kennedy, head of air and environmental quality at the DoE in NI, said: â€œFirst of all it has been particularly cold this week with very little wind â€“ there was a spike in lowland valleys where there was no wind, cold weather and people using more heating. Sometimes people will be burning coal to heat their homes.â€
He added: â€œWe released a number of weather reports last year as well, as we are required to inform residents about air pollution under EU air quality directives.â€
Asked whether there was a plan to deal with spikes in particulate levels in the winter months, Mr Kennedy said: â€œWe have policies in place â€“ thereâ€™s the UK air quality strategy for 2011 and there are a number of local authorities with action plans â€“ they have the power to put policies in place with regards to tackling air pollution.â€
The DoE in NI also published the Air Pollution in Northern Ireland 2011 report earlier this year, which includes a map of the AQMAs in place in the country. This report names Canal Street in Newry as the only monitored site in NI to exceed the annual mean EU particulate matter limit value in 2011 on more than the 25 permitted occasions during the year
However, the DoE believes the measurements for particulate matter in this particular site in Newry may be â€œartificially highâ€.
The report states: â€œAs reported in previous years, there is concern about the location of Newry Canal Street. It is situated in a corner formed by two adjoining buildings, and it is feared that wind vortices can form in the corner, blowing dust into the sampling inlet and leading to artificially high PM10 measurements. (This site is not used for monitoring compliance with the Air Quality Directive.)â€
A statement from Newry and Mourne district council â€“ one of the areas in which high levels of particulate matter were monitored â€“ said: â€œNewry City is set in the basin of a valley and is subject during cold calm periods, as currently being experienced, to episodes of poor air quality. The pollution is a combination of emissions from traffic passing through the city and emissions from heating systems of local housing.Â Within the city we have a network of monitoring sites where nitrogen dioxide and PM10 (particulate matter) is monitored.Â It is from the results of this monitoring that DoE NI issued their recent press statement.â€
The statement continued: â€œThrough a process of assessing local air quality the council has already identified exceedances of the air quality objectives for nitrogen dioxide (annual mean objective) and PM10 (daily mean objective).Â The council has designated Newry urban centre as an Air Quality Management Area (AQMA) for nitrogen dioxide and is to expand this to include PM10.Â We have an agreed Action Plan for the existing AQMA.â€
The councilâ€™s Action Plan includes strategies such as constructing dual carriageways at traffic bottlenecks, enhancing rail services and plans to improve household energy efficiency by encouraging the use of oil and natural gas for fuel instead of coal.
Newry and Mourne district councilâ€™s draft Air Quality Action Plan can be viewed on the council website here.