QA QC Framework
As part of their provision of support to Local Authorities for air quality management, Defra and the Devolved Administrations provide a set of centralised QA/QC services, to assist Local Authorities using diffusive samplers for monitoring of ambient nitrogen dioxide (NO2) concentration, as part of their Local Air Quality Management process.
This is aimed at the analytical laboratories that supply and analyse the diffusion tubes, and currently comprises:
- Promotion of the independent AIR-PT scheme, operated by LGC Standards and supported by the Health and Safety Laboratory, with yearly assessment against agreed performance criteria. AIR-PT combines two long running PT schemes: LGC Standards STACKS PT scheme and HSL Workplace Analysis Scheme for Proficiency (WASP) PT scheme. For more information about the AIR-PT scheme, please click here.
- Operation of a field intercomparison exercise, in which diffusion tubes are co-located with an automatic analyser: from January 2006 this is at a roadside site.
- Provision of quality control standard solutions, free of charge to laboratories that prepare and analyse NO2 diffusion tubes used by Local Authorities for LAQM purposes.
Summaries of participating laboratories' performance in the AIR-PT/WASP scheme over the preceding months, prepared by LGC/BV/NPL, are available by clicking on the links below:
- AIR-PT-Rounds 18 to 28 (Jan 2017 - Oct 2018) (PDF 228KB)
- AIR-PT-Rounds 16 to 27 (Sep 2016 - Aug 2018) (PDF 228KB)
- AIR-PT-Rounds 13 to 24 (Apr 2016 - Feb 2018) (PDF 228KB)
- AIR-PT-Rounds 12 to 22 (Jan 2016 - Oct 2017) (PDF 227KB)
- AIR-PT-Rounds 10 to 21 (Oct 2015 - Aug 2017) (PDF 227KB)
- AIR-PT Rounds 7 to 18 (Apr 2015 - Feb 2017) (PDF 227KB)
- AIR-PT Rounds 6 to 16 (Jan 2015 - Oct 2016) (PDF 226KB)
- AIR-PT Rounds 4 to 15 (Oct 2014 - Aug 2016) (PDF 227KB)
- AIR-PT Rounds 1 to 12 (Apr 2014 - Feb 2016) (PDF 43KB)
- WASP Round 124 and AIR-PT Rounds 1 to 10 (Mar 2014 - Nov 2015) (PDF 43KB)
- WASP Rounds 121 - 124 and AIR-PT Rounds 1, 3, 4 and 6 (Apr 2013 - Feb 2015) (PDF 42KB)
- WASP Rounds 117 - 124 (Apr 2012 - Mar 2014) (PDF 158KB)
- WASP Rounds 116 - 123 (Jan 2012 - Dec 2013) (PDF 157KB)
- WASP Rounds 115 - 122 (Oct 2011 - Sep 2013) (PDF 160KB)
- WASP Rounds 114 - 121 (Jul 2011 - Jun 2013) (PDF 160KB)
- WASP Rounds 113 - 120 (Apr 2011 - Mar 2013) (PDF 159KB)
- WASP Rounds 112 - 119 (Jan 2011 - Dec 2012) (PDF 161KB)
- WASP Rounds 111 - 118 (Sep 2010 - Sep 2012) (PDF 162KB)
- WASP Rounds 108 - 115 (Jan 2010 - Dec 2011) (PDF 43KB)
- WASP Rounds 105 - 113 (April 2009 - June 2011) (PDF 46 KB)
- WASP Rounds 105 - 109 (April 2009 - April 2010) (PDF 118 KB)
- WASP Rounds 104 - 108 (Jan 2009 - Jan 2010) (PDF 119 KB)
- WASP Rounds 103 - 107 (Oct 2008 - Oct 2009) (PDF 121 KB)
- WASP Rounds 102 - 106 (Jul 2008 - Jul 2009) (PDF 137 KB)
- WASP Rounds 101 - 105 (Apr 2008 - Apr 2009) (PDF 137 KB)
- WASP Rounds 100 - 104 (Jan 2008 - Jan 2009) (PDF 121 KB)
- WASP Rounds 99 - 103 (Oct 2007 - Oct 2008) (PDF 119 KB)
- WASP Rounds 98 - 102 (Jul 2007 - Jul 2008) (PDF 121 KB)
- WASP Rounds 97 - 100 (Apr 2007 - Apr 2008) (PDF 132 KB)
Investigation of the Effects of Harmonising Diffusion Tube Methodology
The report (downloadable here) investigates whether harmonisation of preparation and analysis methods for NO2 diffusion tubes has reduced inter-laboratory variation in performance of NO2 diffusion tubes in the UK.
The following report covers an investigation into the effects of harmonising the NO2 diffusion tube methodology by the previous contractor up to 2010. It refers to a rolling performance indicator (RPI) criterion in the discussion of the WASP data. Following a consultation with the participating laboratories HSL has decided to return to the z-scoring system in the future (2011 onwards), and this time will include the percentage of results submitted, which are determined to be satisfactory, based upon a z-score of < ± 2.