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  • Posts dated "February, 2022"

    CASE STUDY - Auchencorth Moss Atmospheric Observatory, Scotland.

    It’s not often we can claim to have supplied samplers to such a scenic location, but in this instance, we certainly can.

    The picturesque landscape (shown below) is home to one of the UK’s most significant research facilities for the study of long-term environmental change.

    About the site

    Auchencorth Moss Atmospheric Observatory (AMo) is a long-term monitoring research infrastructure situated on ombrotrophic peatland based approximately 18km south of Edinburgh. Consisting of 10km2 of patchy mix of grasses and sedges, it lies on a base layer of typical peatland.

    Its purpose is to carry out research on long-term atmospheric composition, surface-atmosphere exchange of pollutants and carbon catchments. As a result of the large number of parameters that are routinely measured at the site, it is part of a wide range of monitoring networks.

    Originally (1994) the site was used to study methane fluxes, the following year studies expanded to include sulphur dioxide and ammonia fluxes due to its peatland ecosystem and distance from emission sources. It has since developed into Scotland’s largest Air Quality Monitoring station being one of only two rural supersites in the UK.

    Today AMo reports over 300 chemical and physical properties of the atmosphere and is used as a platform for many research projects operated by UKCEH Scientists, with all data publicly available on the UK-Air (DEFRA), Scottish Air Quality database, Natural Environment Research Council Data Repository for Atmospheric Science and Earth Observation (CEDA) and EBAS (ebas.nilu.no).

    Monitoring equipment

    With such a large scope of research depending on the site it’s no surprise it’s equipped with state-of-the-art monitoring technology. ET supplied the site with Digitel High Volume (below left) and Low Volume Samplers (below right) over a period of time from 2011 to 2022.

    AMo Instruments

    These sophisticated instruments are ideal for this kind of work. The HVS DHA-80 samplers have an autonomous system for continuous sampling of dust and aerosol particles for later assessment and analysis. Air-borne dust particles in the sampled air are separated on to Ø 150 mm filters so that sequent gravimetric and analytical analysis can be conducted, depending upon the pollutants of interest. The filters are subject to a constant and precise volume flow and are changed automatically at pre-set intervals.

    The LVS DPA14 uses a similar operation, but its execution is 5 to 50 litres per minute (0.3 to 3m³/h as opposed to the 100 - 1000 l/min (6 - 60 m3/h) capacity of the HVS system.

    It’s the superior workmanship in sampler mechanics, backed by the latest technical and electronic control, that guarantees a long lifetime and absolutely reliable operation of these units. And their involvement at facilities such as AMo is a testament to that.

    In addition to the samplers, over the years ET have supplied other high specification instruments to AMo including a Teledyne API T200UP Ultra Sensitive Chemiluminescence Analyser with patented high efficiency Blue Light Converter (BLC) in 2016. The BLC provides a very specific conversion of NO2 with conversion efficiency, avoiding the interferences other methods would be affected by. This allows for consistent and accurate NO2 measurements.

    TAPI T200UP

    For more information on the HVS or LVS samplers from Digitel, or the Teledyne API T200UP Ultra Sensitive Chemiluminescence Analyser available in the UK and Ireland through Enviro Technology Services, check out our website or contact us at info@et.co.uk or ring 01453 733200.

    What sets an ET service contract apart from the others?

    Service Photo

    You‘ve spent a large chunk of your budget on monitoring equipment and can’t risk it failing, not delivering the valuable data you need, right?

    Choosing the right supplier to maintain your considerable investment can be quite daunting, we understand. There’s a lot to consider.

    • How can I be sure the engineer knows the product thoroughly?
    • Can I guarantee a breakdown will be resolved quickly so data loss is minimal?
    • Will spares be available when I need them?
    • Will my service provider be able to service brands supplied by other companies?
    • And, if I’m not satisfied with my current provider, is my contract locked in?

    All these questions, and more are answered in our video – ‘What sets an ET service contract apart from the others’ 

    Serv Cont
    If no extra expenses, no long delays and no fuss is your preference, the choice is clear.

    Benefits in brief
    Nationwide team of engineers covering England, Wales, Scotland and Ireland.

    We’re dedicated to keeping data capture rates at the high levels expected by Government, local authorities and environmental regulators and more than 200 valued customers.

    What sets us apart
    Following almost four decades in the business and with the largest team of air quality monitoring engineers in the UK, we can assure you, it’s our experience, regional coverage and commitment to quality that sets us apart.

    Ultimately, best long-term value for money is what you’ll get with an ET service contract. And that just makes sense.

    To talk to someone about a service contract with ET, call us today on 01453 733240 or email servicecontracts@et.co.uk

    You can also download our service contract brochure here.

    Service Contracts Brochure cover

    Are ozone and sulphur dioxide forgotten pollutants?

    SO2 and O3

    That’s according to ET’s Managing Director and IAQM member, Duncan Mounsor who explains his thoughts on the question below:

    Ask a local authority if they routinely measure ozone (O3) and sulphur dioxide (SO2) and most often, the answer will be no, unless they have a Defra-funded AURN station that includes analysers for these gases in their area.

    But ask them again if they are measuring NOx or PM10 (or PM2.5) and I’d be very surprised if they’re not.

    Both O3 and SO2 are longstanding ‘criteria’ pollutants and WHO, EU and UK national limit values exist for them due to their adverse human health effects. Wet deposition of SO2 falling as acid rain severely damages historic buildings, forests, and freshwater ecosystems, whilst increased O3 concentrations damages vegetation, plants and can lead to substantial reductions in crop yields costing $bn globally.

    We’ve put together some air pollution factsheets which include O3 and SO2 and these can be viewed and downloaded here: https://www.et.co.uk/about-air-quality/air-pollution-factsheets

    O3 and SO2 factsheet image

    Let’s look at O3 and SO2 analyser numbers on the AURN. There are only 25 x SO2 analysers stretched thin across the entire UK. For O3 the numbers fare better, at 70 sites. Compare this to NO2 which is measured at over 145 AURN stations and PM10 and PM2.5 at over 154 stations (combined). Granted, we know now that PM2.5 might be the more dangerous of the pollutants mentioned above in terms of human health, but why isn’t SO2 measured at more sites and locations in the UK, and although there are far more O3 analysers on the network than there are SO2 analysers, why isn’t O3 measured by more local authorities in our towns and cities and more rural areas?

    As our SO2 factsheet explains, there have been massive SO2 emission reductions over the last 30 years as we have quite rightly moved away from coal combustion as our main form of energy generation. It could be argued that the twenty-five SO2 analysers on the AURN are sufficient now for our long-term monitoring.

    Can we largely forget about SO2 now then? Think again.

    Shipping now represents one of the largest global anthropogenic sources of SO2 pollution, and there a lot of ships. A high percentage of your possessions will have been transported to the UK in a shipping container, on a huge container ship, belching out high concentrations of SO2.

    Substantial in-roads have been made by the International Maritime Organisation (IMO) to reduce NOx and SOx emissions from ships, especially when in coastal waters, or SECAs (Sulphur Emission Control Areas) like the English Channel and North Sea. But just like with the vehicles on our roads, ship traffic crossing our oceans, sea-lanes and entering and exiting our ports and harbours is constant, incessant, and increasing.

    Whilst IMO has set down rules about ships having to switch from high sulphur content heavy fuel oil to low sulphur fuel oil when in coastal waters and SECAs, SO2 pollution from ships in our coastal cities and towns could be far higher than we think, and especially in busy ports, harbours, and ferry terminals etc.

    But surely SO2 is routinely measured in urban locations around our long coastline and at all our ports, harbours, and ferry terminals, right? Unfortunately not. Arguments about who should pay for the monitoring equipment, ignorance to the fact that there is a highly probable air pollution problem in the first place, and a myriad of other reasons mean that there is far less monitoring for SO2 than there perhaps should be. Is it a forgotten pollutant, or conveniently just hushed up and swept under the carpet?

    I’m sure the local residents in these areas, especially those suffering from chronic respiratory illnesses, like asthma (which is on the increase in children) might like to know what the SO2 concentration is in the air that they are breathing day after day after day.

    Moving on to another largely forgotten (or ignored) pollutant - Ozone.

    High concentrations of O3 are extremely injurious to human health, damage sensitive ecosystems and have the potential to substantially reduce crop yields, especially at the global scale.

    Increasing numbers of extreme weather events such as prolonged heatwaves can lead to dangerous build-ups of O3. In fact, high temperatures and high concentrations of O3 together present a serious risk to vulnerable groups of people, especially the elderly.

    O3 is transboundary pollutant, and one reason it is not uniformly measured by local authorities is that the sources and generation of ozone may well occur outside of their geographical jurisdictions, with little if anything, for them to be able to do to control, or reduce it locally.

    Feedstock pollutants that along with sunlight lead to the photochemical creation of O3 (i.e. CH4, NOx, VOCs, CO), can be emitted in another location, region, or even another country. In the UK, this pollution can actually come from continental Europe under certain weather conditions, and there’s nothing we can do about it.

    Out of sight, out of mind perhaps?

    In towns and cities, O3 concentrations are kept in check by nitrogen dioxide (NO2) by a series of atmospheric chemical reactions known as REDOX (oxidisation and re-oxidisation).

    NO2 is supplied aplenty from tail-pipe emissions from motor vehicles, so it is typical to generally see higher concentrations of NO2 and correspondingly lower concentrations of O3 – both gases cannot be both present in any significant concentrations at the same time in the same place as the atmospheric chemistry will not permit this.

    However, as we rapidly move forward with the electrification of our vehicle fleet, NO2 concentrations in urban areas will continue to fall, and O3 concentrations from spring and summertime photochemical reactions will increase. That’s chemistry in action!

    This can all be neatly summed up by the UK’s Air Quality Expert Group (AQEG) in their 2021 report on ozone. “As other air pollutants in the UK continue to decline it seems likely that the importance of ozone will grow, especially as its contribution to climate provides further motivation for control measures”.

    In much of the UK, our summertime temperatures now frequently exceed 30°C and often for several consecutive days. And with observed and predicted lower urban concentrations of NO2 creating the conditions to allow more O3 to exist, it unknown exactly how high future concentrations of O3 will climb, but two things are sure:

    One, they are highly unlikely to go down, and two, unless we measure O3 on a more widespread basis than we currently do we won’t actually know exactly what the air quality is like at the local level. And that’s where we live, work and spend our leisure time.

    So, let’s not forget SO2 and O3. They are criteria pollutants for a reason, and need to be measured, perhaps more so than currently.

    Measure four PM sizes simultaneously and with exceptional accuracy with the ES-405 particulate profiler (with Indicative MCERTS pending).

    ES-405 at Upton St Leonards

    Here at ET, we love getting our hands on new products and putting them through their paces in real life tests, so when a demo ES-405 multi-channel particulate profiler landed at the office, and the opportunity to trial it in a residential garden close to the M5 cropped up, we jumped straight on it.

    Fast forward 6 weeks, and we were rewarded with faultless data.

    Data from Upton St Leonards ES 405 study
    With a capability of monitoring in both indoor and outdoor environments, with a choice of 12v battery or mains power, it’s a great choice for numerous applications, including these:

    • Near roadside monitoring

    • Particulate emissions studies

    • Air Quality surveillance

    • Localised particulate data for community health & policy

    • Smart Cities

    • Public and workplace monitoring

    • Plus many more…

    Incorporating a long-life internal sampling pump and large capacity internal data logger, The ES-405 can be set to record data averages from 1-minute to 1-hour. Furthermore, there is an option for the plug and play ‘Cloud Connect System’ so that data can automatically be sent to the internet, for easy access and data downloading.

    One to watch
    This great little rugged, weatherproof, standalone PM profiler measures PM10, PM4, PM2.5 and PM1 simultaneously, in real-time in one instrument with exceptional accuracy and is available at an affordable price.

    We’re very excited about the future of handy little profiler and look forward to being able to supply it with indicative MCERTS very soon!

    For more information on the ES-405 particulate profiler you can watch our video or view the product page.

    DM in es405 vid

    A perfect partnership


    Almost three decades ago ET entered into an exclusive supplier agreement with Met One instruments. It’s a relationship that has proved to be as fruitful as it has long, with considerable sales to the UK market and to many other countries across the globe.

    Where it all began
    Met One Instruments have developed state-of-the-art ambient air quality monitoring solutions since 1989. Our shared relationship with them began back in 1994 with our first order for some Met sensors.

    Over this time, we have sold thousands of Met One products, including:

    • Met sensors - temp, RH, pressure, precipitation, solar radiation, wind speed, wind direction etc. etc.
    • Met sensor data loggers.
    • Hand-held portable particulate profilers for mass-concentration and particulate counting.
    • Small form-factor continuous indicative ambient particulate monitors such as the ES-642, E-Sampler and ES-405.
    • And of course, reference method particulate monitors like the BAM-1020 of which we have sold approx. 600 Worldwide.

    Quality assured
    Met One’s product lines have proven their worth through the years. More than 20,000 BAM-1020 units are currently deployed worldwide, making the unit one of the most successful air monitoring platforms in the world.

    Over the years, the BAM-1020 has evolved with minor changes to maintain approvals. It uses the same industry-proven principle of beta ray attenuation, allowing it to automatically measure and record airborne particulate concentration levels to such a degree of accuracy and reliability that it was the first instrument to obtain U.S. EPA Federal Equivalent Method (FEM) designation for continuous PM2.5 monitoring. Following on, it soon gained corresponding approvals in the European Union (TUV) & MCERTS Continuous Ambient Air Monitoring System & MCERTS for UK Particulate Matter.

    BAM 1020 & cert

    Factory trained
    To ensure customers receive the best support possible, ET sales and service teams travel to Met One’s factory in Grants Pass, Oregon for product and service training. Also, on occasion Met One technical engineers visit ET to provide product and service training to both our workshop and service engineers. This direct knowledge transfer is integral to our commitment to quality.

    Success for the UK’s largest PM monitoring network
    Our long-standing partnership has seen a number of significant tender wins over the years. As of late 2021 the UK’s largest PM network, the AURN (Automatic Urban and Rural Network) consisted of 80 BAM-1020 particulate monitors, all supplied by ET over a period of 20 – 25 years. These make up 60% of the particulate monitors on the network today, with potentially more to add through the 2nd quarter of 2022.

    Other Met One / ET successes
    The ES-642 Particulate Monitor has also proven a very popular product with ET customers. To date we have sold almost 300. Many to dust / vibration / noise specialists for large-scale infrastructure and construction projects

    Es642 on fence copy
    One of the newest additions to the portfolio is the ES-405 particulate profiler (with pending Indicative MCERTS). The ES-405 was developed following ET’s feedback back to Met Ones new product development (NPD) process about the gap in their product line for a simultaneous multi-fraction particulate monitor. It’s this kind of collaboration means we can offer the right product, with quality assurances, to our customers when they need it.

    ES 405 2021 copy

    You can read more about the near reference air quality sensor in our other feature – Measure four PM sizes simultaneously and with exceptional accuracy with the ES-405 particulate profiler (with Indicative MCERTS pending) and watch our video here.

    We’ve enjoyed a great business relationship with Met One over the many, many years we’ve worked together. As one of their longest standing and most successful international distributors in the World, we look forward to continuing the perfect partnership

    UK 3G Networks to begin shutting down in 2023 – Why should I be concerned?

    Say goodbye to 3G

    Skip to the end of this article to find out why you really should be looking to change your air quality monitoring station 3G modem to a modern 4G replacement in 2022, but first, a short history of the evolution of data collection methods since 1990.

    Data collection from air quality monitoring stations.
    Automatic remote data collection from air quality monitoring stations relies on communications technology, and this technology, like all types of technology, is never static for long and always advancing. Dial-up modem, 2G/GPRS, 3G/GSM, 4G/LTE, 5G etc.

    One of the older, but still widely used technologies, 3G is being shut down by Vodafone and EE in 2023 but before we talk more about that and how it might affect you, we thought we’d just provide a short history of the evolution of data collection from air quality stations, as so much has happened, in such a relatively short space of time.

    Before the wireless cellular telephone revolution of the mid-1990’s and well into the 2000’s, data used to be collected over copper wire telephone lines installed into monitoring stations and collected via ‘dial-up’ modems. Who will ever forget the fax-machine type noise of two dial-up modems ‘handshaking’ before data started to flow, at the then super-fast speed of 56kbps!

    US Robotics Fax-Modem anyone?
    Fax Modem
    This was the method of data collection when the UK’s AURN (Automatic Urban and Rural Network) was first established in the UK in 1992 (then just called the AUN). If customers wanted to install a new air quality monitoring station, not only did they need to arrange for electricity to be supplied to the site, but also a hard-wired telephone line. This was complicated and often very expensive with pavements needing to be dug up for telephone lines, in addition to power supplies that also need to be laid.

    And before dial-up modems came on the scene, or if your monitoring stations were in remote locations, you’d probably have to go to the sites and retrieve your data manually, by removing a data logger ‘cartridge’ from an Odessa Engineering DSM 3260 data logger (or similar) or by plugging a direct cable into the back of your logger and firing up your big, old, heavy MS-DOS laptop, if you were lucky enough to have one.

    Logger and cartridge
    And before then, we were in the ancient realms of pen-based chart recorders which were decidedly non-digital!

    As the millennium approached, huge investments were made by the fledgling cellular telecoms companies of the day including Orange, Vodafone, and BT Cellnet.

    As well as primarily carrying voice calls, the cellular networks could also carry packets of data over the airwaves, with no need for telephone cables any longer. Hence the birth of SIM card enabled modems with 2G/GPRS being the first type being used on air quality monitoring stations.

    A 2G/GPRS modem could quickly and easily be connected to a monitoring station data logger, RS232 code activated switch, or directly to the back of an analyser enabling a much more convenient way of collecting data. Much faster than the alternative ‘dial-up’ modem and no need to tie up an expensive landline.

    Then along came cellular ‘smart’ devices like Blackberry’s and then iPhones, heralding the explosion of smartphones onto the market which are now of course, ubiquitous. And all the while our hunger for data and increased ‘bandwidth’ continued to grow.

    It was 3G/GSM that spearheaded the smartphone revolution, and 3G modems meant even faster RS232 communications from data loggers, code-activated switches and analysers used in air quality monitoring stations.
    Maestro M100
    Moving along, the next big step up in speed and bandwidth came with 4G/LTE.

    As well as substantial communication speed and bandwidth hikes, 4G/LAN also enables ‘always-on’ communications. Even if an analyser is located at the other end of the country, or indeed the other side of the world, being internet based, data is always available and accessible from anywhere at any time, night or day.

    As 4G/LAN harnesses the power of the internet and analysers and data loggers are connected via ethernet cables to a 4G (or direct broadband) router, 4G routerthis is the most modern method of data collection from individual gas or particulate analysers, or from a larger AQM system, or even an entire network.


    The image above shows how modern gas analysers, dust analysers and dataloggers can be quickly and simply connected to a 4G/LAN router via ethernet cables. Older non-native LAN analysers can also be connected via ethernet convertors.

    Although 5G is the latest generation of comms technology, it’s roll-out in the UK has been both controversial and political, and it is not yet used (at least to this authors knowledge) in any air quality monitoring stations. Therefore, it will not be discussed here any further.

    Despite 4G/LAN being the most modern method of communication for data collection, 3G modems are still very widely used at air quality monitoring stations, although many forward-thinking data managers, network managers consultants and local authority users have been updating their modems and communications hardware and switching over to 4G.

    And that’s a very good thing to be doing in 2022 as one of the UK’s largest mobile providers, Vodafone, have announced that they will be switching off their 3G network during 2023. EE have also confirmed that their 3G network will also be switched off in this timeframe, and it is expected that the other networks will all follow suit.



    Vodafone message

    So, if you’re still using an old technology 3G modem at your monitoring station, you could well be in for a nasty surprise in 2023 when Vodafone, EE or one of the other providers pull the plug on 3G. Quite simply, your data flow will stop dead in its tracks.

    Next steps
    Thankfully, ET is at hand to help you make the transition to a 4G solution and can provide you options.

    Our advice is not to leave it too late, and to contact us ASAP to speak to an advisor so that a quote can be obtained for the most appropriate 4G solution for your requirements.

    Call us on 01453 733200 or email sales@et.co.uk and we can make sure you are ready for 2023 and beyond.

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