Smog Blog

Celebrating Clean Air Day by monitoring NO2 on the way to work..

Happy ‘Clean Air Day’ everyone! ET encouraged all office based employees to be as environmental friendly as possible on their journey to work today.
Sales Director, Mike Webley walked to walk, with the NEW ET NO2 SmogBox and measured the air quality on his way in to the office, completing a 2 mile stretch in total. The first mile is through residential streets, where pollution levels are low, but the subsequent mile is along the busy A419 road, which has considerably higher pollution levels. Mike says, “Normally when I work to walk, for the 2nd mile I normally walk along the Thames and Severn canal, which is away from the road and the pollution, but today with our SmogBox, I wanted to demonstrate the use of pollution monitoring equipment and how these real time DEFRA MCERTS approved equipment can provide good scientific data.


ET supplies cutting-edge drone based air pollution monitoring technology in the UK.

Watch these videos to see how the Police in Poland have been utilising drone based monitoring technology to sniff-out smog and the use of prohibited fuels.



DOAS Explained

DOAS stands for Differential Optical Absorption Spectroscopy. The DOAS technique was conceived almost a century ago, and it was applied on research level to air quality monitoring already in the 1970s. In the mid-1980s, the technology was then commercialised and turned into practical and wide-spread use.

Read the full Blog article from Opsis here.

The Smogmobile: A Collaboration between the GSMA and the Royal Borough of Greenwich

Back in July this year the Smogmobile was busy helping GSMA and The Royal Borough of Greenwich measure the roadside air quality every minute as it was driven around Greenwich for eight days during two consecutive weeks.

The Smogmobile was used as an experiment to see how a large number of small mobile sensors could potentially map weather and traffic data to understand the causes and fluctuations in air pollution, as oppsoed to the small number of larger fixed AQ stations currently used.

Read the full article here.

ET checks out the new Opsis ‘Real Driving Emissions’ (RDE) on-vehicle testing system

ET’s very own Mike Webley road tests the NEW Opsis RDE (Real Driving Emissions) System in Sweden.

Since the VW ‘Dieselgate’ story broke a few years ago, vehicle emissions have been top of the political agenda. No longer can manufacturers get away with testing in controlled laboratories. Tests are now required in real life, on the road conditions.

With this is mind, Opsis, one of ET’s longest standing suppliers of fast response multi-gas monitoring for air quality and stack emissions have furthered their emissions monitoring portfolio with a system for super fast monitoring ‘on vehicle’ exhaust emissions (CO2, NO and NO2 can also be configured to measure CO, CH4 and even formaldehyde). With easy set up and installation it certainly rivals traditional methods.

For more information on the impressive new RDE system, contact Mike Webley on 01453 733200 or email

Methane emissions from cattle are 11% higher than estimated

The Guardian recently reported that emissions from the greenhouse gas Methane (from livestock), are bigger than previously thought, due to out-of-date data. View the full story here.

Monitoring of methane emissions is crucial when it comes to fighting climate change.

At ET we conducted our own Methane monitoring studies at a diary farm near our offices earlier this year with a Los Gatos Research  UGGA (greenhouse gas analyser) where we discovered levels peaked at 4ppm at certain times, double the ambient background level.

For more information on the LGR Greenhouse Gas analyser (UGGA) view our product page or call us for more information on 01453 733200.

How clean really is the air in Cheltenham? The results are in!

A study of the air quality of an area of Cheltenham very near to the town centre has found it to be better than you might expect.

In June, Duncan Mounsor joined up with St Luke’s resident Bharat Gupta to sample the air in the area during the morning rush hour.

The pair used Duncan’s company’s ‘smogmobile’ a mobile monitoring laboratory built into an electrically-powered Nissan enV200, which produces no emissions itself.

The substances they were looking for were, in particular, nitrogen dioxide (NO2) and PM 10 which stand for ‘particulate matter less than 10 microns in diameter- it’s very fine dust and particles which can do particular damage to human lungs, and for the very smallest particles can get into the bloodstream. And the good news for residents in areas around St Luke’s, London Road, College Road and Bath Road is that these every damaging substances are present in relatively low levels, according to the monitoring.

Read the full story here.

Monitoring Methane on the go has never been easier with the MGGA

Per molecule, methane has a global warming potential 28 times greater than CO2 when considered over a 100-year time horizon, according to a 2014 report by the Intergovernmental Panel on Climate Change (IPCC). When considered over a shorter timeframe of 20 years, the GWP increases to 84 times that of CO2. Methane eventually breaks down in the atmosphere to yield CO2 and water vapour, both greenhouse gases in their own right.

Significant amounts of methane are emitted naturally by sources such as animals, bacteria, and forest fires. More recently, anthropogenic emissions from fracking, waste processing, and leaks in natural gas infrastructure have become another significant contributor to the global methane budget, and the current global average concentration of 1.8 ppm is 250% greater than the pre-industrial era average. With the ever increasing demand for natural gas, emissions from industrial sources are likely to increase further in the near future.

In light of methane’s significant contribution to climate change, measuring it accurately and detecting leaks at the source is more important than ever. A wide variety of equipment exists to measure methane, ranging from highly accurate laboratory instruments such as gas chromatographs, to portable, indicative electronic sensors. One of the major difficulties in monitoring methane emissions arises from the need for fast, highly precise measurements of methane in the field, for instance, in fence line monitoring. Simple semiconductor and infrared based detectors often lack the precision required for these measurements, but laboratory instruments such as GCs are too cumbersome to use on site.

ET is now able to offer a cutting edge, portable methane analyser with a precision of just 3 parts-per-billion to fill this niche – the Los Gatos Research Microportable Greenhouse Gas Analyser (LGR MGGA). The MGGA uses LGR’s patented Off-Axis ICOS detection method, which provides exceptional precision and selectivity with minimal maintenance, and no need for regular recalibrations. In addition to this the MGGA requires no ‘Carrier gases’ or Zero Air unlike FID based instruments. The MGGA, which also measures CO2 and H2O vapour, is built into a rugged, crushproof pelican case with the option of a shoulder strap for easy carrying. There is also an optional telescopic wand for Leak Detection Activities.

With an ultra-fast response, a weight of just 6kg, an internal battery, and the ability to control the instrument using nothing more than a tablet or mobile phone, the MGGA is an ideal tool for leak detection applications. Other applications include; Compliance Monitoring, Air Quality Studies & Soil and Vegetation Flux Studies.

In addition to the 6kg MGGA, ET can offer several alternative methane monitoring solutions from Los Gatos Research, including the popular 15kg Ultraportable Greenhouse Gas Analyser (UGGA), the rack-mounted ‘fast’ greenhouse gas analyser, and alternative configurations capable of measuring CO or NH3, in addition to CH4, CO2, and H2O. Analysers are also available to measure isotopologues of methane and carbon dioxide, for specialist research applications.

University of Brighton poster showing initial results from multi-species Opsis Ambient DOAS System supplied and installed by ET

This poster highlights measurements for the criteria pollutants NO2, O3 and SO2 as well as for HONO (nitrous acid) and Formaldehyde, gases fundamentally important in understanding complex atmospheric processes.

Benefits of the Opsis DOAS system include the ability to measure NO2 “directly” (rather than by calculation by NOx-NO) and also to be able to measure “difficult” gases such as HONO and Formaldehyde on a continuous, hassle-free basis.

As well as providing fast, accurate and inherently reliable measurements, Opsis DOAS requires the absolute bare minimum of operator involvement, a quick wipe of the transceiver and reflector quartz windows once a month is about it!

Coupled with very low running costs, reduced calibration requirements and all the benefits of long-path remote sensing, Opsis DOAS is just one example of the cutting-edge measurement technology available from ET.

You can view the poster here.

Methane Monitoring

The methane produced by approx 35 cows was measured with the Los Gatos Research UGGA (Greenhouse Gas Analyser)  in the smogmobile. Wind speed and direction was also measured and taken into account.

If you require methane monitoring on your farm / site contact ET on 01453 733200



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