QA/QC of Scottish Air Quality Data Ken Stevenson

Project Overview Aim : To have all of the air quality data collected in Scotland in one accessible website Duration: 3-year contract Key elements: Data from National Network and LA sites in Scotland All quality assured to same standard Data available via open access website Long-term trend analysis Mapping of pollutants throughout Scotland Newsletter and Annual Report Annual Seminar

QA/QC of Scottish sites Current Situation – Total 60 Sites on Scottish website (up from 44 in 2007) 32 sites operated under this project 15 AURN 13 funded by LAs or Scottish Grant Scheme

Additional sites to be added 5 sites temporily closed for relocation or roadworks Fife Cupar Edinburgh Haymarket Aberdeen Market St N. Lanarkshire, Harthill N Lanarkshire, Ellis Road 4 sites still to join the database East Lothian, Mussleburgh North High St – In progress East Renfrewshire, Clarkston – In progress Shetland Stanley Hill – telemetry issues North Ayrshire, Irvine – New site recently installed This will bring the total to 69 sites on the Scottish Database.

QA/QC Daily collection of data from each site Scaling of data from last calibration results Daily checking of data On-going data update as new information becomes available Site audits Collection and storage of all calibrations and service records etc 6-monthly data ratification “Quality Circle” data review Update of ratified data to the website Assistance to LAs where-ever possible

Site Audits 2008/9

6-monthly site intercalibration and audit AEA visits every site every 6- months to undertake the intercalibration and site audit Check Analysers Check Calibration Gases Site Infrastructure Local Operator 0401

Problems found at 2008/9 audits Cylinders:- 4 NO cylinders 1 SO 2 Cylinder PM Analysers:- 2 Ko out by more than 2.5% (2.8 – 4.8%) 5 Main flows out (12 – 20%) 6 Leak test failed 1 Aux flow out (26%) Gas Analysers1 CO analyser fail leak test

Feedback from site visits

Data Ratification

Example of Data Summary Sheet

Measuring PM PM 10 “Equivalent Analysers” Partisol (with emfab filters) Beta (Met One) unheated, with correction factor Beta (Opsis SM200) with correction factor TEOM FDMS (not with C drier) (TEOM with Volatile Correction Model)

Partisol  Automated sampling device - size- selected particulate matter on filters for later analysis.  Unattended operation for up to two weeks between site visits.  Filters are equilibrated, at 20° C and 50% R.H., for 48 hours - before and again after sampling.  Filters are carefully weighed using precision microbalances.  Concentration is a function of air volume sampled and weight PM of material on filter.

Scottish Government Partisol Monitoring Programme 2007 PM 10 and PM 2.5 at 5 sites for 1 year Data problems common to all UK Partisol measurements High field blank due to moisture Worst with Quartz filters – even though these are specified in EU PM 10 standard Data now corrected and reported Data used for PM Mapping in Scotland Changed to Emfab filters in AURN

BAM (Beta Attenuation Monitor)  Size-selected particulate matter on filter tape  Analysed by attenuation of Beta rays from Carbon-14 source  Zero from clean filter compared to soiled filter  Algorithm to calculate mass from attenuation  Correction factor may be required for equivalence

FDMS

FDMS Operation Issues Filter Changing Possible long-term problems with FDMS C system Use B or CB type drier

PM 10 Monitoring in the Scottish Database 45 monitors in total FDMS12 BAM4 TEOM 29

Conclusions QA/QC work is key to everything Audits and Ratification are a major part of the project work PM - Partisol issues resolved FDMS and BAM Equivalent PM analysers being deployed We strive to support and work closely with LAs – –respond to requests and enquiries –offer advice –feedback if we see problems with the data –chase for calibrations The database is building rapidly 2006 – ~20 sites 2007 – 44 sites 2008 – 60 sites