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Gas analysis on a bike

A cyclist's exposure to NOx around Cambridge in real-time


With exceedances of permitted NOx levels in many urban environments and the introduction of clean air zones active or planned in a number of cities, the access of delivery vehicles and buses in to such areas has brought their emissions in to sharp focus.  The fitting of defeat devices to obscure Selective Catalytic Reduction (SCR) faults is also a current concern.

Our new fast response NOx analyzer (CLD50) is now portable enough to be carried in a bike trailer and measure the quality of air that our employees are exposed to during their cycle to work.  Note the highly transient peaks of NOx produced by vehicles (especially heavy duty diesel) accelerating away which would not be detectable with this time resolution by conventional portable or roadside measurements.  The effects of single inhalations of such high values are beyond the scope of this study; those working in respiratory medicine might find this interesting.  Later tests also include direct NO₂ measurement (which is more toxic than NO) and also produced from the exhausts of diesels in significant quantities.  Roadside air quality is bound to be impacted until these clouds are dispersed.

Watch the shortened video below:

A cyclist's exposure to NOx around Cambridge in real-time

View on YouTube

Full video available at https://www.youtube.com/watch?v=uzoXW4qDIJI