The ‘Ins and Outs’ of Air Quality

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By Jim Mills
Air Monitors Ltd.

Following the publication of the government’s draft plans to tackle urban air pollution and other publications such as the guidance from NICE on ‘Air pollution – outdoor air quality and health’, Jim Mills, Managing Director of Air Monitors Ltd, explains why there will need to be more funding for monitoring if mitigation measures are to be implemented effectively. Jim also highlights the close relationship between outdoor air quality and the (often ignored) problems with indoor air quality.

In recent years ClientEarth has successfully challenged the government’s air quality proposals in the High Court, and has called for drastic improvements to the draft plan which the government reluctantly published just before the last election. The High Court ordered Defra to produce a final Air Quality Plan by the end of July 2017, but there are major concerns that the plan will fail to bring UK urban air quality in line with EU limits within an acceptable time period.

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. Pressure is mounting therefore on the UK government to increase funding for measures that will have a significant effect on urban air pollution. In particular, there is a need to address the emissions from diesel vehicles which are responsible for high levels of particulates and nitrogen dioxide in the UK’s towns and cities.

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. Local Authorities 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.

Local Authorities 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 Local Authorities 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?

At the recent Air Quality & Emissions show AQE 2017, the Conference speakers were asked about the ‘elephant in the room’, by a delegate referring to the government’s consultation. However, in response Prof. Rod Jones from the University of Cambridge said: “I thought you might be referring to indoor air quality.”

Clearly, urgent action is required to address the problem of outdoor air pollution, but most people assume that they are safe from pollution when they are indoors or in a car, but sadly that is not often the case.

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.

The 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.

The ‘Fidas Frog’, a new fine dust aerosol spectrometer developed by the German company Palas

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.

The new microAeth® MA200 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.

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.

Website: www.airmonitors.co.uk
Facebook: www.facebook.com/AirMonitors
Twitter: @airmonitors
LinkedIn: Jim MillsAir Monitors Limited

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