Latest News

The latest advances in thermal/optical OC-EC particulate matter monitoring technology available from ET.

Exclusive UK & Ireland distributor for Sunset Lab, Enviro Technology Services Ltd, would like to introduce the latest editions to its product portfolio. The Model 4 Semi-Continuous OC-EC (Organic Carbon and Elemental Carbon) carbon analyser from Sunset Laboratory Inc, incorporates the latest advances in electronic and optical technology, along with an optimized oven and detector designed for sensitive and reliable field operation. It’s also rack mountable.

Features include an easy access panel for filter service and calibration, safety mechanisms and inline pressure regulators for superior flow control. The computer controlled flow system aids enhanced sensitivity and fast analysis times and improved user access for simplified maintenance and service.

It’s small, rugged design makes it ideal for field operation in air quality monitoring shelters.

The Sunset Laboratory Model 4 OC-EC Field Analyser is ideal for:

  • Ambient air quality and environmental exposure measurements
  • Indoor air exposure assessment monitoring
  • Long-term environmental research such as studying the effects of regulatory changes
  • NIOSH (and equivalent) exposure assessments in the workplace

In addition to the Model 4 Field Analyser the Model 5 Lab OC-EC Aerosol Analyser is also now available via ET.

The Model 5 uses a proven thermal-optical method to analyse for organic and elemental carbon aerosols collected on quartz filters.

Features include a temperature controlled diode laser, an integrated 16-bit data system/CPU board, redesigned power control hardware, automated flow controls, and software making this the most reliable OC-EC analyser on the market.

The samples are thermally desorbed from the filter medium under an inert helium atmosphere followed by an oxidizing atmosphere using carefully controlled heating ramps.

A flame ionization detector (FID) is used to monitor the analysis. Proven low dead volume carrier gas control system and proprietary quartz oven design provide high sensitivity with ultra-low carbon background and no oxygen contamination.

This instrument has been used to analyse a wide variety of sample types, including: ambient urban and rural areas, national parklands, forest fire plumes and oil fires from the Gulf War.

It is the industry standard for environmental and workplace monitoring.

For further information on the Sunset Lab Model 4 Field Semi-Continuous OC-EC Carbon Analyser or the Model 5 Lab OC-EC Aerosol Analyser contact or ring us on 01453 733228.

New BSI ISO 9001:2015 Certification for Enviro Technology

Stroud based air quality monitoring equipment and service provider, Enviro Technology Services Ltd, have recently made the successful transition from ISO9001:2008 to the latest version of the standard, ISO9001:2015.

The scope of ET’s BSI accredited ISO9001 Quality Management System covers “the design, manufacture, installation and servicing of environmental monitoring systems and associated equipment” and the certificate is valid until September 2018.

ET’s Managing Director, Duncan Mounsor explains “we have held our ISO 9001 quality certification for almost 20 years so having this certification is nothing new for us, but that said, we are pleased that the hard work that we put in for the transition to the new 2015 revision to the standard has paid off as there are only a few companies to have made the transition so far, and even fewer (if any) in the environmental monitoring sector”.

ET also operates BSI accredited and certified ISO 14001 environmental and OHSAS 18001 health and safety management systems.

Mounsor continues “quality is fundamentally important at ET; quality of products, quality of service and at every level within the business. And operating in the environmental sector it is essential for us to walk-the-walk and not just pay lip-service with regards to our environmental impacts and we are proud of our environmental achievements to date. These include changing our entire fleet of diesel estate cars to petrol-electric hybrids as well as a programme of changing all the fluorescent tubes in our head office over to LED panels which we are midway through.

Mounsor concludes “customers and stakeholders increasingly expect businesses to work to high quality, documented and externally audited management systems for quality, environment and health & safety. At ET, our accreditation and certification for all three of our systems is with BSI, one of the world leading, top-tier certification bodies who we are proud to align ourselves with. Having these systems requires top management commitment, investment and hard work and they are audited each year by BSI at their surveillance visits. We could have made the decision to go down the cheaper, easier, non-accredited self-audit road with our management systems, but feel that our customers, stakeholders and employees deserve more. It is all about continuous improvement at ET and that is what drives us forward.

** End **

New remote sensing LIDAR technology helps ET aim for the sky!

When it comes to air pollution measurement, ET has been leading the way, bringing innovative and cutting-edge instrumentation to market since its inception in 1983.

ET has always been an advocate of remote-sensing, for instance, using short or long-path optical technology to quantify gas concentrations over distances ranging from a few metres (for vehicle emissions monitoring) through to several hundreds of metres for urban, fence-line and fugitive emissions monitoring.

Examples include the Accuscan RSD vehicle emissions monitoring system that measures the individual exhaust emissions of each and every vehicle that drives through the cross-road optical path and the Opsis DOAS system that enables multi-gas measurements from single or multiple open paths in ambient air.

Most recently, ET has formed an exclusive partnership with Sigma Space Incorporated from the USA and has been busy trialling the amazing mini-MPL system which stands for micro-pulse LIDAR. Sigma Space know a thing or two about remote sensing as the MPL was originally developed by NASA and instead of remote sensing looking down (i.e. from a satellite), the MPL, and now the mini-MPL, is ground based, looking upwards.

Designed to be housed in a small, temperature controlled weatherproof enclosure, the mini-MPL has a maximum vertical range of up to 15 km. That is about 9 miles for those who prefer non-metric units. It is therefore able probe up to the highest extents of the troposphere and beyond and with a minimum accumulation time of 1 second, builds up a detailed and dynamic profile of the atmosphere providing data on planetary boundary layer (PBL), cloud types (heights and tops) rain, ice-crystals and aerosol i.e. volcanic ash, Saharan dust as well as anthropogenic particulate matter etc.

The mini-MPL is amazing in many ways. Firstly, it is very small (hence the mini bit). It stands just less than 0.5 m high and weighs just 13 kg. Second, power consumption is very low at just 100 W. Third, it is classified as eye-safe. Fourth, it is a fraction of the cost of the large, power hungry LIDAR’s of days gone by and fifth, it is remarkably easy to use. Non-LIDAR specialists can be up-and-running with it in minutes and the Sigma Space analysis software makes simple work of understanding and presenting the wealth of information coming back from the 532 nm green eye-safe laser.

During 2017, ET will be demonstrating and trialling the mini-MPL at several leading Universities and working with some of the country’s leading LIDAR specialist and atmospheric scientists in order to showcase the huge capabilities and range of applications for this novel technology. Applications include; early warning of volcanic ash for airports, dynamic PBL monitoring, atmospheric aerosol research, weather forecasting and meteorology and even source apportionment of industrially generated particulate.

For more info, call the ET Sigma Space product specialists, Duncan Mounsor and Lewis John on 01453 733200 or email




LGR’s Microportable Gas Analyser (MGGA) reports measurements of methane, carbon dioxide and water vapor simultaneously in a package that is compact, crushproof and travels anywhere.

The MGGA is simple to use which makes it ideal for natural gas leak detection and other field studies, compliance monitoring, air quality studies and soil flux studies, and wherever measurements of methane, carbon dioxide and water vapor are needed quickly and sensitively.

You can view the advert here and the product page here.

Contact ET for further details 01453 733200

Revealed: top Tories' constituencies suffer blight of toxic air

Toxic air that breaches the EU legal limit is blighting the constituencies of Theresa May and at least five other Cabinet ministers, an Evening Standard investigation reveals today.

The Standard  hires a ToxicAirTracker (the Smogmobile) — a pollution-monitoring van from Enviro Technology Services, to tour seats held by Cabinet ministers before Parliament was dissolved and they ceased being MPs.

Read the full story here.

ET wins Teledyne-API Top European Sales Award

Enviro Technology Services Ltd (ET) have been announced as Teledyne-API’s (TAPI) top performing European distributor for 2016.

The Stroud based company was recognised not only for selling the largest number of TAPI air quality gas analysers in Europe during 2016 but also for their sterling efforts promoting and selling TAPI’s latest range of  “next-generation” instruments and calibrators, including the T500U CAPS direct-reading NO2 analyser and the T750 portable dilution calibrator.

The award was presented to ET’s Managing Director, Duncan Mounsor and Sales Director, Mike Webley at the TAPI EMEA Distributor meeting held in Nice, France on the 4th May 2017.

Reflecting on the prestigious award, Duncan Mounsor said “on behalf of everyone at ET we are proud to receive this award as it recognises both the hard work put in by the ET sales team and our projects and customer service teams who have delivered and installed a record breaking number of projects over the last 12 months in the UK”.

Duncan concludes “a large part of ET’s success is having great products to sell such as those from our long-standing technology partner, Teledyne-API. Coupled with the fact that TAPI analysers offer such high levels of performance, reliability, 2-year warranty (5 years on some items) and great technical support, our job is made all the more simpler”.

For more information on any of Teledyne-API’s gas analysers, please contact the ET Sales Team on 01453 733200 or email

If your looking for a Service Contract, our new brochure will tell you all you need to know.

Download brochure here

NEW T200P Photolytic NO2/NO/NOx Analyser

ET are pleased to introduce the NEW T200P Photolytic NO2/NO/NOx Analyser with patented high efficiency Blue Light Converter (BLC), also known as a photolytic converter.

The T200P is based on the standard T200 analyser but uses a photolytic LED array BLC converter to convert NO2 to NO rather than a traditional catalytic (stainless steel) or chemical reagent (molybdenum) based converter.

This may sound a bit complicated, but what does it mean in practice?

Being far more “specific” (and therefore with less measurement uncertainty) means that NO2 measurements are made more accurately and precisely than from regular chemiluminescent NOx analysers which are known to overestimate NO2 by up over 50% in some applications.

And as the T200P also measures NO, then users have the best of both worlds, precise and accurate NO measurements with enhanced NO2 measurement performance.

Perfect for roadside and urban background sites, especially those that are close to, or exceed the annual NO2 limit value of 40 µg/m3.

And if “true” direct NO2 measurement is what you are looking for, and don’t necessarily need the NO channel, then check out our most advanced NO2 analyser, the MCERTS approved T500U CAPS analyser.

For more information on the T200P (or any other of our NO2 and NOx analysers) call ET on 01453 733200 to speak to one of our specialists or download our handy NOx analyser comparison brochure at

The T500U CAPS NO2 Analyser - Now with added MCERTS

In 2015 ET announced the availability of the latest technology in ambient and trace level NO2 measurement with the T500U CAPS (Cavity Attenuated Phase Shift) direct reading NO2 Analyser, capable of “true” NO2 measurements across the ranges 0-5ppb through to 1 ppm.

We are now very pleased to report that the T500 has acquired MCERTS certification.

Now, along with our standard NOx monitor the T200 and the Ulra-sensitive T200UP (with photolytic converter) ET can offer an alternative to Chemiluminescence for those requiring MCERTS certification.

Representing the next generation of criteria pollutant monitoring technology for the direct measurement of Nitrogen Dioxide in air, the T500U CAPS measurement approach vastly reduces the amount of maintenance required whilst directly measuring NO2. Other benefits include, fast response, exceptional measurement sensitivity and low power consumption (80 Watts).

The T500 joins the Opsis System 300 open-path system (also sold by Enviro Technology) as one of only two non-chemiluminescent NO2 analyser techniques to receive UK ambient MCERTS certification.

ET upgrades the AURN with BAM1020 PM analysers

In March 2016, Bureau Veritas - in its role as Central Management and Co-ordination Unit of the UK Automatic Urban and Rural Network - on behalf of DEFRA, purchased a number of BAM1020 PM analysers from Enviro Technology Services for both PM10 & PM2.5 to replace existing TEOM analysers on the AURN under the ET trade-in offer, providing good value for money.

Sales Director, Mike Webley said, ET has been offering equipment trade-in for a number of years to Local Authorities, & we were pleased to offer a similar contract to the national network.

We all love summer

 At Enviro Technology Services Plc we pride ourselves on supplying top end, quality products to a market that requires accurate data for research projects using traditional reference methods of measurement. However, we do of course recognise that there are other opportunities for more indicative, cost effective solutions needed for certain applications.

For example: We all love the summer but there are a few downs sides to the wonderful weather that we need to be aware of.

Have you ever considered the health impacts of Barbequing for instance? It’s yet another form of air pollution and if you live in an area already suffering the effects of heavy traffic, like London, then seemingly small acts like barbequing can contribute considerably, especially when done in concentration.

For comparison, a recent study in the states noted that a diesel-engine lorry would have to drive 10 miles to produce the same amount of pm2.5 particles as a single char grilled burger.  (Researchers at the University of California)


Barbecuing is banned in many London Parks now as a result of local residents complaining of health related issues attributed to large numbers of people barbecuing in parks nearby on warm days. Research has shown a huge increase in PM2.5 levels when this occurs.

Of course there are other contributing factors to increases in particle matter in the air, including waste transfer stations, build-up of traffic outside schools during drop off and pick up and construction dust from residential developments, the list goes on.

Enviro Technology is offering the perfect solution for those needing to measure PM2.5 , PM10 or TSP particles from such situations - 
The Neighborhood Monitor from Met One.

It’s a simple, affordable, wireless solution. The purchase price includes everything you need:

  • Hardware
  • Sim cards
  • 3 years web access

All you need to do is turn it on.

Below is an example of a typical cloud application showing location, tabulated data and charts.
(Data output can be tailored to your needs)

Keep up to date

Contact Us

Like to make an enquiry or ask a question? Or simply have a suggestion about how we could improve our customer service, we'd love to hear from you!