T300U Ultra-Sensitive Gas Filter Correlation CO Analyser (Trace Level)

The Model T300U Ultra-Sensitive CO analyser has been developed specifically to address the challenges of low level monitoring as required, for example, in the US NCore network. Using IR absorption with a Gas Filter Correlation Wheel, the T300U is designed to allow ultra-sensitive CO measurements while still meeting the requirements for use as a US EPA compliance analyser.

• Ranges: 0-100 ppb to 0-100 ppm, user selectable
• Lower Detectable Limit: < 20 ppb

T200U Ultra-Sensitive Chemiluminescence NO/NOy Analyser (Trace Level)

The Model T200U NOy analyser has been developed and refined specifically to address the challenges of NOy monitoring as required, for example, in the US NCore network. It uses the proven chemiluminescence principle and is coupled with a remote NOy converter via umbilical to allow measurements with a lower detectable limit of 50 ppt.

• Ranges: 0-5 ppb to 0-2,000 ppb, user selectable
• Lower Detectable Limit: <50 ppt

T200U Ultra-Sensitive Chemiluminescence NO/NO2/NOx Analyser (Trace Level)

The Model T200U Ultra-Sensitive NO/NO2/NOx analyser has been developed specifically to address the challenges of low level monitoring as required, for example, in the US NCore network. It uses the proven chemiluminescence principle and is designed to allow ultra-sensitive measurements with a lower detectable limit of 50 ppt while still meeting the requirements for use as a US EPA compliance analyser.

• Ranges: 0-5 ppb to 0-2,000 ppb, user selectable
• Lower Detectable Limit: 50 ppt

T100U Ultra-Sensitive UV Fluorescence SO2 Analyser

The Model T100U Ultra-Sensitive SO2 analyser has been developed specifically to address the challenges of low level monitoring as required, for example, in the US NCore network. It uses the proven UV fluorescence principle, and is designed to allow ultra-sensitive SO2 measurements while still meeting the requirements for use as a US EPA compliance analyser.

T700U Dynamic Dilution Calibrator

The Model T700U is a microprocessor based calibrator for precision gas analyzers. Using highly accurate mass flow controllers combined with compressed sources of standard gases, calibration standards are provided for multipoint span and zero checks using up to 4 gas sources.

In addition to the features of the Model T700, the Model T700U is designed for the demanding requirements of ultra-sensitive measurements.

T700 Dynamic Dilution Calibrator

The Model T700 is a microprocessor based calibrator for precision gas analysers. Using highly accurate mass flow controllers combined with compressed sources of standard gases, calibration standards are provided for multipoint span and zero calibrations using up to 4 gas sources.

• Generates precise calibration gases for SO2, H2S, NO, NO2, CO, O3, and others

T400 UV Absorption O3 Analyser

The Model T400 UV Absorption analyzer uses a system based on the Beer-Lambert law for measuring low ranges of ozone in ambient air.

• Ranges: 0-100 ppb to 0-10 ppm, user selectable
• Lower Detectable Limit: < 0.6 ppb

T300 Gas Filter Correlation CO Analyser

The Model T300 measures low ranges of carbon monoxide by comparing infrared energy absorbed by a sample to that absorbed by a reference gas according to the Beer-Lambert law.

• Ranges: 0-1 ppm to 0-1000 ppm, user selectable
• Lower Detectable Limit: 0.04 ppm

T200 Chemiluminescence NO/NO2/NOx Analyser

The Model T200 NO/NO2/NOx analyser uses the proven chemiluminescence detection principle, coupled with state-ofthe- art electronics to allow accurate and dependable low level measurements for use as an ambient analyser or dilution CEMS monitor.

• Ranges: 0-50 ppb to 0-20 ppm, user selectable
• Lower Detectable Limit: 0.4 ppb

T100 UV Fluorescence SO2 Analyzer

The Model T100 uses the proven UV fluorescence principle, coupled with a state of the art user interface to provide easy, accurate, and dependable measurements of low level S02.

• Ranges: 0-50 ppb to 0-20 ppm, user selectable
• Lower Detectable Limit: 0.4 ppb

Currently Under Construction

A study taken over 16 years by German researchers, has shown that those exposed to higher levels of traffic related air pollutants over a period of time are more likely to develop type 2 diabetes.

1,175 middle-aged German women living in urban and rural areas were closely studied and found that those living near major roadways were twice as likely to develop type 2 diabetes.

The researchers pinpointed nitrogen dioxide (NO2) and the soot in ambient fine particulate matter (PM) – two components of traffic pollution – as primary culprits.

The women who were exposed to higher levels of traffic-related pollution at the beginning of the study were more likely to have developed diabetes at follow-up. In fact, the risk of diabetes increased by 15-42 percent for every 25 percent increase in traffic exposure.

The study is one of the first to follow participants over many years in order to look at whether traffic-related air pollution might be linked to the risk of developing diabetes later in life. It agrees with a handful of prior human and animal studies that have suggested a link between the two.

Although this study was conducted on women, the German researchers who authored note that they would expect no significant difference in results for a similar study conducted on men.

This is just one more in the long list of traffic pollution related diseases such as asthma and chronic bronchitis.

Since 1983 ET has been providing national and local government with Air Quality Analysers & systems. We believe that cutting down on emissions has never been so important.

Opsis AQM System at Tower Bridge

Due to the well-proven evidence that correlates high PM levels with mortality rates, the answer is probably no, but NO_2, and more specifically “direct NO₂” seems to be a real hot potato at the moment.

If you have been to any of the recent high profile IAQM and EPUK conferences over the last few months, chances are you will have sat through one of the many “direct NO₂” presentations that are currently doing the rounds. These have been delivered by AQ luminaries such as Dr David Carslaw (ERG Kings College) and Dr James Tate (ITS Leeds University) to name but a few.

So what is all the fuss about?

Well, as we all know, it is widely accepted that NOx levels in urban areas have been falling steadily over the last 10 years. So along with drastic reductions in CO levels as well over the same period, this surely bodes well for local air quality management, right?

Well, not exactly.

Recent studies and data collected from several urban and kerbside AURN stations show, that although overall NOx levels are down, NO₂ levels are worryingly on the up at certain “hot-spots” across the UK.

Leading academics and consultants, now think they know why, and it would appear it is primarily down to “direct NO₂” tailpipe emissions.

Sadly, our love affair with the motor car is still as healthy as ever and incentives to kick-start some life into the struggling motor industry, like the UK’s highly successful “scrappage scheme” have in fact had a detrimental effect in our on-going battle to improve air quality in some areas. So too has been the “dieselisation” of the vehicle fleet over the last 10 years (i.e. PM₁₀).

Why is that then?

Well, the motor manufacturing industry is targeted, through the Euro engine classification system (i.e. Euro IV, Euro V and now Euro VI) to reducing amongst others, NOx, PM and CO₂ emissions for new vehicles. NO₂ has traditionally only been a very small part of the overall NOx emission, and clean engine technology has been refined, developed and rolled out now to ensure our overall NOx emissions are within the EU Euro specs. However, approximately 40% of vehicles sold these days are diesels and as we all know, diesel vehicles produce much higher levels of those “killer” PM₁₀ particles then petrol engine vehicles and so the motor manufacturers have had to come up with ways in keeping PM₁₀ levels in check too.

So how do they do that and what has it got to do with NO₂?

Well, we have all heard about catalytic converters and particulate traps etc. The latter mainly work by “burning” the particles before they come out of the tailpipe. It is a thermal oxidisation process.

When you burn air, the nitrogen compounds get converted to NO₂ and this, is the heart of the problem.

In a major drive to help reduce CO₂ emissions, diesel car uptake has never been so high. This is fuelled (no pun intended) by the HMRC CO₂ scale and Benefit in Kind taxation system for company car drivers. Essentially, you stand to pay far less tax if your company car is of the diesel type.

And it is not just cars, the London Low Emission Zone has forced taxi and HGV owners and operators to comply with new rules that have on one hand, ensured that our buses, HGV’s and taxi’s are cleaner (in terms of CO₂ and particulates) but they are all adding to the growing direct NO₂ problem.

So in a nutshell, in terms of NO₂ at least, recent studies have demonstrated that some of the new cars that have come into service during the scrappage scheme (over 400,000 vehicles), many emit far higher levels of NO₂ than the 10 years + old ones that they have replaced!

Sure, the NOx, PM10, HC emissions are demonstrably lower, but not necessarily NO₂.

This conundrum is causing a major headache for Defra and the Air Quality Helpdesk, who at this moment in time, do not know how to advise worried Local Authorities who ask, what can we do about this?

One thing that is for sure, is that it is very complicated and extremely difficult to model future NO₂ levels. I recently heard that one leading UK University ran a 27-dimensional model on its biggest, fastest super-computer and it took a few days to do some number crunching.

And then there are the model uncertainties. Getting a result that is within +/- 20% accuracy I’m told is very good indeed. And what do we validate the models with?

The answer to that is that we use diffusion tubes and Chemiluminescent NOx analysers.

But that is OK isn’t it?

Well that depends on your point of view…

VHS was OK before DVD came along, cathode ray TV’s were OK before Plasma/LED TV’s came along, the slide rule was probably OK before the pocket calculator came along (but I’m too young to remember those).

Chemiluminescent NOx analysers are OK, and to many, they are the “Gold Standard” for NOx monitoring, and diffusion tubes? Well that is a whole other debate.

Now the focus is squarely on NO₂, and chemiluminescent NOx analysers have one fundamental problem and that is they don’t actually measure NO₂ at all, instead they convert NO₂ back to NO using a high temperature molybdenum converter at approximately 315 ^OC. The sample gas is actually switched either through the moly converter or directly into the reaction cell thereby giving us the NOx – NO = NO₂ measurement equation.

In theory this is great, but it is dependent on certain assumptions and critical factors. The first of which is that moly converter is efficient. In a perfect world, this efficiency should be 100% but in practice it may be closer to 95% on a well maintained, modern NOx analyser and could be far less on older analysers or those that are not serviced frequently or maintained and calibrated adequately.

The second consideration is measurement uncertainty. Again, in an ideal world, every part of the analyser, calibration system and sampling system should be studied and all the “uncertainties” added up to give an overall expanded uncertainty which we should then use as a measure of quality assurance.

Thirdly moly converters can also convert other nitrogen compounds into NO, not just the NO₂. The catalytic technique is not 100% selective to NO₂ only, so any other oxides that are inadvertently converted to NO will be “calculated” as NO₂ even if they are not really.

Chemiluminescent NOx analysers, like all what we call “point” analysers are a hybrid pneumatic/electronic box of tricks that sample a relatively small volume of sample air (i.e. 800cc/min) using sample lines (of varying lengths and conditions), pumps (in various states of operational condition) and solenoid valves, flow restrictors, critical orifices, sample inlet filters, converters, catalysts, scrubbers and a myriad of other things.

All of these components have a bearing on measurement uncertainty and what comes in at the end of the sample tube, will never get to the detection part of the analyser 100% intact. There are losses, chemical reactions and interferences all along the way.

So how sure are you now that the 25 ug/m3 NO₂ that your NOx analyser is displaying really is 25?

OK, so what alternatives are there to the good old Chemiluminescent NOx box?

Surprisingly few is the answer to that, and even fewer that “really” work for low-level ambient air quality monitoring applications.

However where all this is leading us to is something called UV DOAS!

UV what??

UV DOAS, or to give it its full name Ultra-Violet Differential Optical Absorption Spectroscopy.

Firstly, UV-DOAS is a non-contact, non-pneumatic optical system that measures NO₂ “directly” and many other gases (such as O₃ SO₂ and BTEX) in real-time over for example a 500m open-path in ambient air.

Using three main components, an emitter, a receiver and a small, compact DOAS analyser (a computer controlled UV spectrometer) DOAS detects and measures target gases by analysing their unique spectral absorption characteristics (think of it as a sophisticated gas fingerprinting system).

Each gas has its own unique “fingerprint” and DOAS is able to look at the ones of interest and these only. It not only computes the gas concentration but also the standard deviation of each measurement, which is a major quality assurance improvement over “standard” analysers that pretty much expect you to “gauge” the overall quality after you have worked out all those measurement uncertainties touched on briefly above.

DOAS is fast, inherently accurate, requires no sampling system, the minimum of calibration (six-monthly is more than adequate) and more importantly is far more representative of local air quality levels than for instance, the data generated from a single NOx analyser, after all, it is monitoring a much larger sample (several hundered meters of air) as opposed to perhaps 800cc/min from a single inlet head.

It has also got the right credentials as it internationally approved and validated and in the UK has an MCERTS certificate for NO₂ SO₂ O₃ and Benzene.

Gas molecules are as we know, very small. The NO₂ molecules that we are trying to measure with our chemiluminescent NOx analysers when mixed up in ambient air are almost mind-bogglingly well dispersed and distributed. Just think about the nomenclature that we use, for instance “parts per billion”. Think about it, this means one NO₂ molecule in one billion parts of air.

Sure, if we find a few of the NO₂ molecules in ambient air, our chemiluminescent analysers are sensitive enough to measure them (after being converted back to NO first of course) but what if those molecules evade capture through our relatively puny 800 cc/min sample lines?

Well they won’t get measured.

Molecules will, and do, do their own thing. They are here one second, somewhere else the next, (the realm of the quantum) and if they are 1,5,10 or 100m from your NOx analyser sample inlet, the fact is, they won’t get measured. To get measured, they need to be pretty much floating about right by your sample inlet system, and then they might even slip away if the wind changes!

But imagine a beam of light running alongside the busy road we want to take our NOx measurements from, let’s say 300m long for arguments sake. We know the NO₂ levels are high in this area from our modelling or diffusion tubes surveys. Just think of all those NO₂ molecules that will be potentially present in that 300m section of horizontal air mass we are shining our light through. Chances are we are going to do a far better job of finding them and measuring them in a far more representative manner than from our single chemiluminescent NOx analyser.

Chances are however, that the real concentrations might actually be higher (or lower) than we expect as we now have a system that is far more adept and representative than before.

However, to coin another well used phrase “to measure is to really know” and now that the UK is facing all manner of well reported problems with cities such as London reported by some quarters to be the most polluted city in Europe, isn’t it time that we took a fresh look at alternative monitoring technologies?

After all, who still uses VHS, Cathode Ray TV’s and slide rules..

To find out more, call ET on 01453 733200 and ask to talk to someone about Opsis open-path.

Alternatively email sales@et.co.uk and visit our website www.et.co.uk

Duncan Mounsor, Sales & Marketing Director, Enviro Technology Services Plc.

ENDS

Paul Wilson, BOC Special  Gases Morden (London)

Patrick Pisani
GDF Suez

Ben Rose
Manchester City Council

Best regards
Phillip R.Jones
AQ Data Services

HVS Blower DS-02

Controlled High Volume blower for autonomous and continuous measurements.

The DIGITEL blower DS-02 is a part of a system to sample dust and aerosol particles for later assessment and analysis. The sampler operation range in standard execution is 100 to 1000 litres per minute (6 to 60 cubic metres per hour). The system’s usual designation is „High Volume Sampler“.

Air-borne-dust parts in the sampled air are separated onto 150 mm diameter filters. The flown filter diameter is 140 mm. Subsequent gravimetric and analytical analysis could be conducted depending upon the pollutants of interest. Filter material and structure selection (deep filters, porous filters, glass fibres, silica fibres, pulp, Teflon, porosity….) will depend on the analysis purpose. The filter conditioning is important in order to achieve reproducible results.A flow meter controls the selected air flow rate. This value should be calibrated first at the beginning of a measurement session, using a gasmeter or a secondary standard, e.g. an additional flow meter. During air sampling, the pump flow rate is dynamically controlled, so that this value is kept at good reproducibility and at long-term stability despite the deposited filter flow resistance and the sampled ambient air pressure / temperature variation.

An integrated microprocessor unit controls filter changes at the exact preset time and collects all relevant data and events. Hereby the air quantity flowing through the filter is defined with high accuracy.

For more information and technical data see http://www.digitel-ag.com/Frameset_engl.htm

HVS single filter unit DH-77

High Volume Sampler (HVS) Single filter unit for autonomous and continuous measurements.

The Digitel High Volume Sampler DH-77 is a system to sample dust and aerosol particles for later assessment and analysis. The sampler operation range in standard execution is 100 to 1000 litres per minute (6 to 60 cubic metres per hour). The system’s usual designation is „High Volume Sampler“.

Air-borne-dust parts in the sampled air are separated onto 150 mm diameter filters. The flown filter diameter is 140 mm. Subsequent gravimetric and analytical analysis could be conducted then depending upon the pollutants of interest. Filter material and structure selection (deep filters, porous filters, glass fibres, silica fibres, pulp, Teflon, porosity….) will depend on the analysis purpose. The filter conditioning is important in order to achieve reproducible results.

For more information and technical data see http://www.digitel-ag.com/Frameset_engl.htm

Digitel HVS Automat DHA-80

High Volume Sampler (HVS) for autonomous, continuous measurements.

DIGITEL DHA-80 is a system for sampling dust and aerosol particles for later assessment and analysis. The sampler operation range in standard execution is from 100 – 1000 l/min (6 – 60 m³/h). The system is usually called „High Volume Sampler“.

Various models of samplers are available from different applications. Generally, they differ by the number of filters processed and by the type of logging failure indication and status messages as well as by the type of remote control via various interface protocols.

Air-borne dust particles in the sampled air are separated on to Ø 150 mm filters. The flown filter diameter is 140 mm. Sequent gravimetric and analytical analysis could be conducted depending upon the pollutants of interest. Filter material and structure selection (deep filters, porous filters glass fibres, silica fibres, pulp, Teflon, porosity…) will depend on the analysis purpose. The filter conditioning is important in order to achieve reproducible results.

DHA-80 has a container of 15 filters stretched in filter holders. They are changed automatically to the flow position at the pre-set time.

2750 Methyl Mercury Distillation System

Enviro Technology introduces Tekrans new Model 2750 Methyl Mercury Distillation System.

The Tekran  2750  is designed to be compact and modular, reducing the required bench top footprint. The Tekran 2750 has the following unique features:

• Distillation system offers 30-position preparation, fully compliant with EPA method 1630
• Robust gas flow control system significantly reduces operating cost
• Actively cooled water bath eliminates the need for ice, avoiding the associated inconveniences
• Precision PID temperature controlled aluminium heating block
• Programmable timer turns of the heater, chiller and purge gas supply at completion of distillation cycle
• Heating block lid prevents sample reflux in distillation vials
• Modular design provides flexibility; gas distribution panel can be wall mounted

For futher information contact Enviro Technology at info@et.co.uk or ring us on01453 733200

For more information about our full range of products and services see www.et.co.uk

All hire equipment is thoroughly tested, calibrated and fully prepared prior to delivery and ET can even provide installation and commissioning services. We can also provide local site operation (LSO) service and data collection and data management for clients.

Analysers / Systems Available For Hire / Rental.

• Teledyne API M100 A/E  UV Fluorescent SO2 Analysers
• Teledyne API M200 A/E Chemiluminescent NOx Analysers
• Teledyne API M300 A IR-GFC CO Analysers
• Teledyne API M400 A/E UV Absorption O3 Analysers
• BAM1020 beta-attenuation PM10 particulate Analysers
• BAM1020 beta-attenuation PM2.5 particulate Analysers
• MiniVOL Portable PM10/PM2.5/TSP Samplers
• Sven Lekel SEQ 47/50 CEN12341 Sequential Gravimteric Sampler.
• Sven Lekel LVS-3 CEN12341 Single Fliter Sampler.
• OPSIS AR500 UV DOAS multi-gas open-path monitoring system for BTEX, SO2, NO2, O3.
• Data loggers.
• Communications systems including GPRS, GSM and modem.
• Meteorological sensors and masts.

ET can also offer a wide range of mobile and static air-conditioned weatherproof enclosures.

• PR4, PR5 and PR10 size Roadside Enclosures.
• Twin axled trailers.
• Groundhog trailer including roof mounted OPSIS open-path AQM system.

The 2700 offers a fully integrated, self-contained compact unit based on atomic fluorescence detection and operated via state-of-the-art software.

• Superior Atomic Fluorescence Detector
• Export Support
• Designed for Flexibility
• Intuitive Software Interface

• Highly sensitve, ultra-stable CVAFS Hg detector.
• MDL of 0.004 ppt (25 mL sample).
• Built-in GC oven (isothermal or ramped heating).
• IR trap heating and active cooling.
• Syringe drive for precise volumetric injection.
• Liquid detector halts system if water enters gas lines.
• Heated volume manifold prevents potential losses.
• Interfaces to ICP-MS to yield isotopic rations of methyl mercury.

If you need to talk to someone about how to fill out this form them please call Jim Budd or Phil Battye.

The Accuscan 4600 system

The Accuscan 4600 system measures vehicle emissions in real time by using optical gas and particulate monitoring technology, set up at exhaust pipe height on the side of the road.

AEROCET 531 Handheld Particle Mass Profi ler & Counter

The Aerocet 531 is a small, handheld, batteryoperated, and completely portable unit. This unit provides both particle counts or mass PM measurements as stored datalogged values, real-time networked data, or printed results.

GT - 526 Handheld Particle Counter

The GT-526 is a full-featured, battery-operated, portable laser particle counter that provides the functionality of a bench unit with the convenience of a handheld! It can datalog particle counts continuously or send them to a network.

GT-521 Handheld Particle Counter

The GT-521 is a full-featured, battery-operated, portable laser particle counter that provides the functionality of a bench unit with the convenience of a handheld! It can datalog particle counts continuously or send them to a network.

GT-321 Handheld Particle Counter

The handheld GT-321 is a portable particle counter that counts particles down to 0.3 microns—giving you portability and reliability at the lowest price in the industry.

IAQ Surveyor

With 90% of our time spent indoors, determining the quality of the air we breathe indoors is essential for good health and productivity. The IAQ Surveyor II and IAQ Surveyor Pro monitor key indoor air quality indicators including carbon dioxide, humidity, temperature and carbon monoxide. Should these measurements fall outside recognized guidelines, further tests can be made to suggest an appropriate course of action. For example, ventilation studies show that as room temperatures rise above 75°F(24°C) the ability of occupants to concentrate can drop by up to 50% and high levels of carbon dioxide will indicate poor ventilation that results in drowsiness and perceived stuffiness. Both situations are very common and seriously affect productivity. Over-ventilation wastes energy and results in increased building running costs.

BAM 1020

With over 250 units sold in the UK to date, the BAM1020 continues to be one of the best selling particulate monitors in the UK. This is down to several reasons.

• Excellent value for money. The BAM1020 is extremely cost-effective, to buy, operate and run. The sample tape lasts for 60 days providing hourly mass measurments so local site operation in only required once every 2 months.
• Compact, rugged and reliable. The BAM1020 has been in production for over 15 years and has earned an excellent reputation internationally for it’s reliability, accuracy and ease of use.
• EU/UK Approved equivalent method for use on all UK monitoring networks. The BAM1020 was one of only a selct few instruments tested to comply with the CEN 1234-1 reference method during the 2005 BV inter-comparison.

If you are thinking in investing in a new PM monitor or upgrading or exchanging your current particulate monitor to ensure EU equivalency/compliance contact ET today for a discussion on how the BAM1020 can save you time, money and complication!

The BX – 970 Touch screen Display User Interface Option for the BAM1020.

Classic BAM-1020 functionality. Easier and simpler to use.

The BX-970 option consists of a new high-visibility touch screen PC module built into a redesigned BAM-1020 front door assembly. All of the existing functionality of the BAM-1020 is retained in a more modern, logical, and intuitive format for easier menu navigation.

The BX-970 option is recommended for locations where the basic BAM-1020 display is difficult to see, and for users who frequently navigate the menu system to change or adjust operational settings.

The new Synspec Alpha Benzene is a very simple but precise Benzene only analyser.

A potential hazard in the aluminium smelting industry is the release of hydrogen fluoride (HF) and other gas emissions.

• HF- Hydrofluoric Acid
• Pot Room Analysis
• CEMS