The UK Government's Department for Environment, Food and Rural Affairs has set up a framework for Local Air Quality Management (LAQM) and Local Authorities widely use nitrogen dioxide (NO₂) diffusion tubes for Indicative monitoring to calculate annual NO₂ concentrations for Review and Assessment purposes. The European Union under directive 20/50/EC on ambient air quality and cleaner air for Europe provides data quality objectives both for Indicative and Fixed measurements of NO₂.

LAQM diffusion tube measurements across the UK between 2015 & 2019 were analysed to see if they had been providing data of sufficient quality to be classed as Indicative measurements in support of Local Air Quality Management. Bias corrected annual averaged measurements delivered uncertainties compared to the reference method of <±25%, therefore demonstrating that application of the National bias adjustment factors are providing valid Indicative diffusion tube measurements for the UK.

For the full calendar year 2020, the equivalence of the monthly UK Urban NO2 Network (UUNN) diffusion tubes were analysed. The UUNN style diffusion tube is similar to the LAQM style but with the addition of an amorphous polyethylene (PE) filter across the open end of the tube. Results showed that the Network meets the EU Directive uncertainty requirement for Fixed measurements (±15%), without the need for slope or intercept correction. Mean NO₂ concentrations derived from triplicate UUNN tubes show a much better precision than the triplicate conventional LAQM tubes.

A field determination of the diffusive sampling rate for UUNN tubes was performed at London Marylebone Road, showing that the sampling rate in real world conditions was very similar to that determined in the laboratory.

Diffusion tube data form Belgium and Germany were also analysed for equivalence with the Standard Reference Method to help put the UK results into context.

英国政府环境、食品和农村事务部建立了地方空气质量管理 (LAQM) 框架，地方当局广泛使用二氧化氮 (NO ₂ ) 扩散管进行指示性监测，以计算年度 NO ₂浓度以供审查和评估目的。欧盟根据关于欧洲环境空气质量和清洁空气的指令 20/50/EC 为 NO _{2 的}指示性和固定测量提供了数据质量目标。

分析了 2015 年至 2019 年英国各地的 LAQM 扩散管测量结果，以查看它们是否提供了足够质量的数据，以被归类为支持当地空气质量管理的指示性测量结果。与参考方法相比，偏差校正的年平均测量值产生的不确定性<±25%，因此表明国家偏差调整因子的应用为英国提供了有效的指示性扩散管测量值。

对于 2020 年整个日历年，分析了每月英国城市二氧化氮网络 (UUNN) 扩散管的等效性。UUNN 型扩散管类似于 LAQM 型，但在管的开口端增加了无定形聚乙烯 (PE) 过滤器。结果表明，该网络满足欧盟指令对固定测量的不确定性要求 (±15%)，无需斜率或截距校正。来自一式三份 UUNN 管的平均 NO ₂浓度显示出比一式三份常规 LAQM 管更好的精度。

在伦敦马里波恩路 (London Marylebone Road) 对 UUNN 管的扩散采样率进行了现场测定，表明现实世界条件下的采样率与实验室中测定的采样率非常相似。

还分析了来自比利时和德国的扩散管数据与标准参考方法的等效性，以帮助将英国的结果纳入上下文。