The ‘ins and outs’ of air quality monitoring!

20/02/2017
The British National Institute for Health and Care Excellence (NICE) recently issued draft guidance on ‘Air pollution – outdoor air quality and health.’ 

Here, Jim Mills, Managing Director of Air Monitors Ltd, explains why there will need to be more funding for monitoring if the mitigation measures mentioned in the guidance are to be implemented effectively. Jim also highlights the close relationship between outdoor air quality and the (often ignored) problems with indoor air quality.

The NICE guidelines are being developed for Local Authority staff working in: transport, planning, air quality management and public health. The guidance is also relevant for staff in healthcare, employers, education professionals and the general public.

Covering road-traffic-related air pollution and its links to ill health, the guidelines aim to improve air quality and so prevent a range of health conditions and deaths. Unfortunately, on the day that the draft guideline was published, most of the national media focused on one relatively minor recommendation relating to speed bumps. ‘Where physical measures are needed to reduce speed, such as humps and bumps, ensure they are designed to minimise sharp decelerations and consequent accelerations.’ Measures to encourage ‘smooth driving’ are outlined; however, the guidelines also address a wide range of other issues, which, in combination, would help tackle urban air pollution.

Public sector transport services should implement measures to reduce emissions, but this is an area that could involve the greatest financial cost.

Many local authorities would doubtless comment that they are already implementing many of the guideline recommendations, but refer to budgetary constraints on issues that involve upfront costs. This issue was raised on BBC Radio 4 when the issue was discussed on 1st December.

AQMesh Pod

AQMesh Pod

The NICE guidelines recommend the inclusion of air quality issues in new developments to ensure that facilities such as schools, nurseries and retirement homes are located in areas where pollution levels will be low. LAs are also urged to consider ways to mitigate road-traffic-related air pollution and consider using the Community Infrastructure Levy for air quality monitoring. There are also calls for information on air quality to be made more readily available.

LAs are also being urged to consider introducing clean air zones including progressive targets to reduce pollutant levels below the EU limits, and where traffic congestion contributes to poor air quality, consideration should be given to a congestion charging zone. The guidelines also highlight the importance of monitoring to measure the effects of these initiatives.

As part of the consultation process, NICE is looking for evidence of successful measures and specifically rules out “studies which rely exclusively on modelling.”

In summary, all of the initiatives referred to in the NICE report necessitate monitoring in order to be able to measure their effectiveness. However, most LAs do not currently possess the monitoring capability to do so. This is because localised monitoring would be necessary before and after the implementation of any initiative. Such monitoring would need to be continuous, accurate and web-enabled so that air pollution can be monitored in real-time. AQMesh is therefore the ideal solution; small, lightweight, quick and easy to install, these air quality monitors are able to monitor all the main pollutants, including particulates, simultaneously, delivering accurate data wirelessly via the internet.

Whilst AQMesh ‘pods’ are very significantly lower in cost both to buy and to run than traditional reference stations, they still represent a ‘new’ cost. However any additional costs are trivial in comparison with the costs associated with the adverse health effects caused by poor air quality, as evidenced in the recent report from the Royal College of Physicians.

Inside Out or Outside In?

Fidas® Frog

Fidas® Frog

The effects of air pollution are finally becoming better known, but almost all of the publicity focuses on outdoor air pollution. In contrast, indoor air quality is rarely in the media, except following occasional cases of Carbon Monoxide poisoning or when ‘worker lethargy’ or ‘sick building syndrome’ are addressed. However, it is important to understand the relationship between outdoor air quality and indoor air quality. Air Monitors is currently involved in a number of projects in which air quality monitoring is being undertaken both outside and inside large buildings, and the results have been extremely interesting.

Poorly ventilated offices tend to suffer from increased Carbon Dioxide as the working day progresses, leading to worker lethargy. In many cases HVAC systems bring in ‘fresh’ air to address this issue, but if that fresh air is in a town or city, it is likely to be polluted – possibly from particulates if it is not sufficiently filtered and most likely from Nitrogen Dioxide. Ventilating with outdoor air from street level is most likely to bring air pollution into the office, so many inlets are located at roof level. However, data from recent studies indicate that the height of the best air quality can vary according to the weather conditions, so it is necessary to utilise a ‘smart’ system that monitors air quality at different levels outside the building, whilst also monitoring at a variety of locations inside the building. Real-time data from a smart monitoring network then informs the HVAC control system, which should have the ability to draw air from different inlets if available and to decide on ventilation rates depending on the prevailing air quality at the inlets. This allows the optimisation of the internal CO2, temperature and humidity whilst minimising the amount of external pollutants brought into the indoor space. In circumstances where the outside air may be too polluted to be used to ventilate, it can be pre-cleaned by scrubbing the pollutant gases in the air handling system before being introduced inside the building.

Fidas200The implementation of smart monitoring and control systems for buildings is now possible thanks to advances in communications and monitoring technology. AQMesh pods can be quickly and easily installed at various heights outside buildings and further units can be deployed internally; all feeding near-live data to a central control system.

Another example of indoor air quality monitoring instrumentation developing from outdoor technology is the ‘Fidas Frog,’ a new fine dust aerosol spectrometer developed by the German company Palas. The Frog is an indoor, wireless, battery-powered version of the hugely popular, TÜV and MCERTS certified Fidas 200. Both instruments provide simultaneous determination of PM fractions, particle number and particle size distribution, including the particle size ranges PM1, PM2.5, PM4, PM10 and TSP.

Evidence of outdoor air pollution contaminating indoor air can be obtained with the latest Black Carbon monitors that can distinguish between the different optical signatures of combustion sources such as diesel, biomass, and tobacco. The new microAeth® MA200 for example, is a compact, real-time, wearable (400g) Black Carbon monitor with built-in pump, flow control, data storage, and battery with onboard GPS and satellite time synchronisation. Samples are collected on an internal filter tape and wireless communications are provided for network or smartphone app integration and connection to other wireless sensors. The MA200 is able to monitor continuously for 2-3 weeks. Alternatively, with a greater battery capacity, the MA300 is able to provide 3-12 months of continuous measurements.

In summary, a complete picture of indoor air quality can be delivered by a combination of AQMesh for gases, the Palas Frog for particulates and the microAeth instruments for Black Carbon. All of these instruments are compact, battery-powered, and operate wirelessly, but most importantly, they provide both air quality data AND information on the likely source of any contamination, so that the indoor effects of outdoor pollution can be attributed correctly.

@airmonitors #Environment #PAuto @_Enviro_News


Particulate monitors selling like hot cakes.

03/12/2016

Palas, the German manufacturer of particulate monitoring instruments, is expanding production to cope with demand for its fine particulate monitor, the Fidas® 200. In the following article Jim Mills explains why Air Monitors, the British distributor, is being kept busy by the demand for this exciting new technology.

fidas_200PM monitoring – the ultimate goal
We monitor PM because of its acute health effects. It irritates our eyes and lungs, and some of the finer particles were more recently shown to be able to move directly from the nasal cavity to the brain. Monitoring is therefore essential, but there are almost as many monitoring methods as there are types of PM, so it is vitally important to monitor what matters. If you are measuring dust from a construction site, the PM is relatively large in diameter and heavy, but if you are monitoring PM from diesel emissions in a city, the smallest particles with much less mass but high particle numbers, are of greater interest. Monitoring a single size fraction provides an incomplete picture of particulate contamination and risks ignoring the PM of most interest, particularly if the ignored fractions are the finer particles that travel deepest into the lungs. The ideal PM monitor would therefore reliably and accurately monitor all important PM fractions, with high data capture rates and low service requirements… hence the heavy demand for the Fidas 200.

Fidas® 200
The Fidas 200 is a fine dust ambient air quality monitoring device, developed specifically for regulatory purposes; providing continuous and simultaneous measurement of PM1, PM2.5, PM4, PM10, TSP (PMtot), as well as particle number concentration and particle size distribution between 180nm and 18µm (further non-certified size ranges are also available on request).

Employing a well-established measurement technology – optical light scattering of single particles – the Fidas 200 is equipped with a high intensity LED light source, which is extremely stable, delivering a long lifetime, with minimal service requirements. An optical aerosol spectrometer determines the particle size using Lorenz‐Mie scattered light analysis of single particles. These particles move through an optical measurement volume that is homogeneously illuminated with white light, and each particle generates a scattered light impulse that is detected at an angle of 85° to 95° degrees. The particle number measurement is based on the number of scattered light impulses, and the level of the scattered light impulse is a measure of the particle diameter.

The Fidas 200 operates with a volume flow of approx. 0.3m3/h and is equipped with a Sigma‐2 sampling head, which enables representative measurements even under strong wind conditions. The sampling system includes a drying system that prevents measurement inaccuracies caused by condensation from high humidity, which means that it will continue to function correctly in misty or foggy conditions but without the loss of semi-volatile fractions of the PM. It is also equipped with a filter holder for the insertion of a plane filter (47 or 50 mm in diameter) which enables subsequent chemical analysis of the aerosol.

Different versions of the Fidas 200 allow for stand-alone outdoors installation or for installation inside a measurement cabinet or air quality monitoring station.

Performance
The Fidas 200 is the only ambient continuous PM monitor in the UK to have passed TÜV and MCERTS. The MCERTS certificate (Sira MC16290/01) confirms that the Fidas 200 complies with the MCERTS Performance Standards for Continuous Ambient Air Quality Monitoring Systems, and with MCERTS for UK Particulate Matter. The instrument has type-approval to the Standards EN 12341 (PM10), EN 14907 (PM2.5) and is certified to the Standards EN 15267-1 and -2.

Importantly, the FIDAS 200 has half the uncertainty of many of its rivals and one third of the required uncertainty (25%).

Typical data capture rates exceed 99%. This has been achieved by a design approach that is focused on reliability. For example, two pumps operate in parallel, providing redundancy protection, and the instrument continuously monitors status and calibration.

Monitoring frequency has an adjustable time resolution ranging from 1 second up to 24 hours. However, high frequency data provides almost real-time access to readings when deployed with a remote web-enabled Envirologger. This enables the detection of short-term spikes, providing much greater insight into the causes of PM pollution.

The Fidas instruments have been proven in many countries as well as Britain; Air Monitors has been supplying Fidas PM monitors for around three years and there are now over 30 monitors in operation Britain alone.

Costs
One of the major financial considerations for Fidas 200 is its extremely low operating cost; the requirement for consumables is almost nil (no filter required) and its power consumption is around one fifth of its nearest rival. Calibration can be checked and adjusted, if necessary, quickly and easily in the field with a simple monodisperse powder test.

The purchase cost of a single Fidas 200 is a little more than some ambient PM monitors, but it is less expensive than others. However, for most instruments, a requirement to monitor two fractions, say PM2.5 and PM10, would necessitate two instruments and therefore double the cost. With budgets under pressure, Fidas therefore provides an opportunity to obtain better data for less cost.

In summary, the Fidas 200 offers better performance than all of its rivals; usually at significantly lower capital cost and always with dramatically lower operational costs. Consequently, it is no surprise that these instruments are selling like hot cakes.

@airmonitors #PAuto @_Enviro_News


Air pollution – the invisible roadside killer.

14/12/2015

The VW emissions scandal has helped to raise awareness of the deadly threat posed by air pollution in many of our towns and cities. In the following article, Jim Mills, Managing Director of Air Monitors, an instrumentation company, explains why diesel emissions will have to be lowered and how the latest monitoring technology will be an essential part of the solution.

Background
The World Health Organisation has estimated that over 500,000 Europeans die prematurely every year as a result of air pollution – especially fine particulates from combustion processes and vehicles. Of these, around 30,000 are in Britain; however, experts believe that the figures could be substantially higher if the effects of Nitrogen Dioxide (NO2) are also taken into consideration.

London Smog - now less visible!

London Smog – now less visible!

Historically, air pollution was highly visible, resulting in air pollution episodes such as the Great London Smog in 1952. However, today’s air pollution is largely invisible (fine particulates and NO2 for example), so networks of sophisticated monitors are necessary.

The greatest cause for alarm is the air quality in our major towns and cities where vehicles (main diesels) emit high levels of NO2 and particulates in ‘corridors’ that do not allow rapid dispersion and dilution of the pollutants. Urban vehicles also emit more pollution than free-flowing traffic because of the continual stopping and starting that is necessary.

As a result of its failure to meet European air quality limits, the Government was taken to the UK Supreme Court in April 2015 by ClientEarth, an organisation of environmental lawyers. In a unanimous judgement against Defra (English Department for Environment, Food and Rural Affairs), the Court required the urgent development of new air quality plans. In September 2015 Defra published its Draft Air Quality Plans, but they have not been well received; respondents have described them as disappointing and unambitious. CIWEM (The Chartered Institution of Water and Environmental Management) , an organisation representing environmental management professionals, for example, said: (the plans) “rely on unfunded clean air zones and unproven vehicle emission standards.”

Some commentators believe that Defra should follow Scotland’s lead, following the publication, in November 2015, of ‘Cleaner Air for Scotland – The Road to a Healthier Future’ (CAFS). Key to this strategy is its partnership approach, which engages all stakeholders. Under CAFS, the Scottish Government will work closely with its agencies, regional transport partnerships, local authorities (transport, urban and land-use planners and environmental health), developers, employers, businesses and citizens. CAFS specifies a number of key performance indicators and places a heavy emphasis on monitoring. A National Low Emission Framework (NLEF) has been designed to enable local authorities to appraise, justify the business case for, and implement a range of, air quality improvement options related to transport (and associated land use).

Traffic-related air pollution
In addition to the fine particulates that are produced by vehicles, around 80% of NOx emissions in areas where Britain is exceeding NO2 limits are due to transport. The largest source is emissions from diesel light duty vehicles (cars and vans). Clearly, there is now enormous pressure on vehicle manufacturers to improve the quality of emissions, but urgent political initiatives are necessary to address the public health crisis caused by air pollution.

A move to electric and hybrid vehicles is already underway and developments in battery technology will help improve the range and performance of these vehicles, and as they become more popular, their cost is likely to lower. The prospect of driverless vehicles also offers hope for the future; if proven successful, they will reduce the need for car ownership, especially in cities, thereby reducing the volume of pollution emitting vehicles on the roads.

Vehicle testing is moving out of the laboratory in favour of real-world driving emissions testing (RDE) which will help consumers to choose genuinely ‘clean’ vehicles. However, the ultimate test of all initiatives to reduce traffic-related air pollution is the effect that they have on the air that people breathe.

Ambient air quality monitoring
Networks of fixed air quality monitoring stations provide continual data across the UK, accessible via the Defra website and the uBreathe APP. Many believe that this network contains an insufficient number of monitoring points because measurement data has to be heavily supplemented with modelling. However, these reference monitoring stations, while delivering highly accurate and precise data, are expensive to purchase, calibrate and service. They also require a significant footprint and mains electricity, so it is often difficult or impossible to locate them in the locations of most interest – the pollution hotspots.

Public sector budgets are under pressure, so the cost of running the national monitoring network and those systems operated by Local Authorities is a constant source of debate. The challenge for technology companies is therefore to develop air quality monitors that are more flexible in the locations in which they are able to operate and less costly in doing so.

Air Monitors’s response

New technology
Air Monitors has developed a small, battery-powered, web-enabled, air quality monitor ‘AQMesh’, which can be quickly and easily mounted on any lamp post or telegraph pole at a fraction of the cost of traditional monitors. Consequently, for the first time ever, it is possible to monitor air quality effectively, where it matters most; outside schools, on the busiest streets and in the places where large numbers of people live and breathe.AQMesh_podAQMesh ‘pods’ are completely wireless, using GPRS communications to transmit data for the five main air polluting gases to ‘the cloud’ where sophisticated data management generates highly accurate readings as well as monitoring hardware performance. In addition, it is now possible to add a particulate monitor to new AQMesh pods.AQMesh does not deliver the same level of precision as reference stations, but this new technology decreases the cost of monitoring whilst radically improving the availability of monitoring data, especially in urban areas where air quality varies from street to street.The flexibility of these new monitors is already being exploited by those responsible for traffic-related pollution – helping to measure the effects of traffic management changes for example. However, this new level of air quality data will also be of great value to the public; helping them to decide where to live, which routes to take to work and which schools to send their children to.

Keeping all Welsh air good!

25/06/2014
Air quality monitors track pollution hot-spots

Situated in the south west of Wales, in a largely rural area bordering the Brecon Beacons, Carmarthenshire’s air quality is predominantly good. However, there are areas of concern where major roads pass through some of the County’s larger towns, including Llanelli, Carmarthen and Llandeilo, where air quality is dominated by the effects of road traffic. The County Council is therefore testing new monitoring technologies so that it will be better able to track the effects of improvement measures.

The sensor!

The sensor!

Carmarthenshire County Council operates a network of passive diffusion tubes as part of its commitment to Local Air Quality Management under Part IV of the Environment Act 1995. However, in 2013, Air Monitors supplied the Council with a new type of air quality monitor, ‘AQMesh’, that is able to provide continuous air quality readings for a range of important parameters. This new technology is small, wireless, lightweight and battery powered, which means that it can be quickly and simply mounted in almost any location.

The Council’s monitoring programme has identified Nitrogen Dioxide (NO2) from traffic emissions, mostly diesel vehicles, as the pollutant of greatest concern. A number of locations in the centre of Llandeilo have been shown to be in breach of European air quality standards, so an Air Quality Management Area (AQMA) has been established in the town. Whilst NO2 levels are not sufficiently high to cause immediate health effects, the current levels could cause adverse health effects over the long term, particularly in people suffering from respiratory conditions such as asthma and chronic obstructive pulmonary disease.

NO2 reduction by about 25µg/m3 is the main objective of the air quality action plan, but the Council is determined to ensure that all pollutants remain at safe levels, so the ability of the AQMesh to monitor a wide range of parameters (Ozone, Carbon Monoxide, Sulphur Dioxide, Nitrogen Monoxide, Nitrogen Dioxide, Temperature, Humidity and Atmospheric Pressure) is a major benefit.

Four features
Stephen Hoskin from Air Monitors says: “There are a number of important new features in AQMesh that are fundamentally changing the way that air quality is monitored; firstly, it can be located where air quality matters most – where people are breathing.

“Secondly, in comparison with large reference stations, with only a small drop in levels of accuracy, the cost of monitoring is reduced dramatically, which means that users will be able to measure air quality in more locations, and this will reduce the UK’s current dependence on modelling to ‘guesstimate’ air quality.

The unobtrusive sensor in situ!

The unobtrusive sensor in situ!

“Finally, by providing near real-time data over the internet, useful air quality data can be made available to a much wider audience via smartphones, tablets and computers.”

The AQMesh in Carmarthenshire is being operated by Oliver Matthews, one of the Council’s Environmental Health Practitioners with specific responsibility for air quality. He says: “In the past we have not continuously monitored this range of parameters because doing so would have involved the installation of a large, expensive air quality monitoring station that would have probably required planning permission.

“These reference stations offer high levels of accuracy, but come with large capital and operational costs, and cannot typically be moved, whereas the AQMesh can be quickly attached to a lamp post or other item of street furniture at a fraction of the cost.

“Alternatively, we could install passive diffusion tubes, one for each parameter of interest, but the disadvantage of this method is that the tubes are left in place for four to five weeks, so we are only provided with an average figure over that time, with no indication of the peaks and troughs that occur. For example, a recent road closure resulted in the diversion of traffic and, with the benefit of AQMesh, we were able to track a significant short-term rise in NO2.”

With the assistance of key stakeholders, the AQMA draft action plan has identified a number of options to improve air quality, and the AQMesh unit has been installed in order to help assess the success or failure of each initiative.

Interestingly, the development of the AQMA action plan benefitted from essential gas main works that were required in Llandeilo because this involved the closure of the main trunk road (Rhosmaen Street) for a period of up to three months, which provided an opportunity to identify the effects of traffic diversions on air quality.

Options that are being considered as part of the action plan include improving traffic management and seek to prevent vehicular ‘stop/start’ and promote a smooth flow of traffic. Typically, these options could include the provision of extra parking outside of the AQMA, the removal of some on-road parking within the AQMA, better parking enforcement, relocation of bus stops, reviewing pedestrian crossings and improvement of bottle necks.

Summarising Oliver says: “The network of diffusion tubes has enabled us to identify hotspots, and these are the locations at which the AQMesh will be of greatest use because we will be able to study trends and look for the causes of elevated pollution levels at specific times of the day.

“Data from the AQMesh are provided on a website via the ‘Cloud’ so, looking forward, this technology has the potential to make a major difference to air quality improvements and to the transparency and availability of data. For example, it may become possible to integrate air quality monitoring with automatic traffic management.”


Black carbon

14/10/2011
Air quality specialist calls for Black Carbon standard

Traditionally, ambient particulates have been measured gravimetrically according to their size. However, Jim Mills, Managing Director of Air Monitors, believes that the time has come to change or at least augment the way ambient particulates are monitored and regulated.

Read about Black Carbon on Wikipedia!

Black carbon is in the air and circulates the globe.

Black Carbon (BC) is a term describing the fine particles that are produced as the result of incomplete combustion of fuels and Jim contests that new BC measurement standards would radically improve human health AND make a very significant contribution to the fight against climate change. BC can be measured accurately and specifically with an Aethalometer, which provides a real-time readout of the concentration of ‘Black’ or ‘Elemental’ carbon aerosol particles in the air.

Health Issues
Despite dramatic reductions in airborne particulates in recent decades, a significant level of human health problems persist, and many scientists now believe that finer particles may be the major cause because they are able to travel deeper into the respiratory system.

Climate Change

Black Carbon monitor

The MicroAeth Model AE51 is the worlds first ever real-time, pocket-sized Black Carbon aerosol monitor.

BC stays in the atmosphere for a relatively short period of time – from days to weeks. This is important because BC emissions are the second largest contribution to current global warming, after carbon dioxide emissions. However, since carbon dioxide stays in the atmosphere for many decades, emissions reductions will take a long time to have an effect, which means that efforts to reduce BC could have a much faster impact on global warming.

Research
The importance of BC has been recognised by the European Commission which is funding a new research project (CARBOTRAF) which aims to create a method, system and tools for adaptively influencing traffic flow in real-time to reduce CO2 and BC emissions caused by road transport in urban and inter-urban areas.

The two host cities Glasgow (GB) and Graz (A), were chosen due to their ability to manage traffic flows and utilise real-time air quality monitoring systems from Air Monitors and a decision support system provided by IBM Inc.

Summary
Historically, initiatives to lower airborne particulates have been driven by a regulatory need to reduce the levels of PM10 particulates, so new additional monitoring standards based on BC could drive improvements that would both enhance human health and help in the fight against climate change.

The Aethalometer® is an instrument that uses optical analysis to determine the mass concentration of Black Carbon particles collected from an air stream passing through a filter. These particles are directly emitted to the air during all combustion, but are primarly associated with coal or diesel smoke. They adversely affect public health; contribute to local and global climate change; and reduce visibility. Aethalometers are used by air-quality monitoring programs; public-health protection agencies; research laboratories; and community groups.

Aethalometer data contribute to an understanding of the composition and sources of air-pollution particles; the effects of poor air quality on public health; and the effects on local weather and global climate change.

The Aethalometer technology is available on different chassis and platforms: Rack Mount, Portable, Modular, High Range, and Transmissometer. The Aethalometer is also offered in two configurations of light analysis: 2-Wavelength (infra-red 880 nm for Black Carbon; ultraviolet 370 nm for aromatic organic compounds) and 7-Wavelength (7 sources from 370 nm to 950 nm).