Mining sites are generally dusty places – but how dusty? Is the health of workers at risk, could local communities be affected or operations compromised? As well as high levels of particulate matter, mining facilities may also generate pollution from other activities, such as engines producing oxides of sulphur or nitrogen.

To add potential complication, there may be other sources of the same pollutants in the same area, as well as vulnerable communities. A reliable air quality monitoring system can provide a clear and confidential picture of air pollutant levels at a mining site. Continuous pollutant readings from across and around a project offer real insights to inform operations.

A practical air quality monitoring tool that’s up to the job

AQMesh pods can be installed – with no training – in ten minutes, as they come with simple post fittings and have autonomous communication, using the local phone network to transmit data to a cloud server. Whilst direct power supply is an option, the smart solar pack offers reliable 12-month power in most locations, and is equally easy to set up. 

Mines are notoriously tough sites, with high dust levels, use of heavy machinery and dust suppression spraying. AQMesh has been designed and proven to withstand not only these challenges but the worst that nature can present. Long-term monitoring around mining facilities from Saudi Arabia and Australia to Sweden and Canada has demonstrated robust performance in hot and dry to freezing conditions. 

Meaningful air quality information to support operations 

A real-time view of pollution, which can be related to operational activities and events, can provide unique insights into how your operations are – or are not – impacting local air quality. Identifying peaks of pollutants by exact time of day and location brings some hard facts into any question of air quality levels around the site or over the boundary towards neighbouring communities.  

As well as creating a valuable historical record of measured pollution levels, near real-time readings can be used to trigger exceedance alerts, evaluate dust mitigation measures or provide data for compliance to local environmental standards. Measurement accuracy is underlined by indicative MCERTS certification for PM2.5 and PM10. 

Scope to go further 

Whilst even a single pod can answer many questions about air pollution around a mining facility, it is possible to set up a larger network of pods around a site. AQMesh can also be used alongside other measurement technologies, including passive sampling, bag samples or reference / equivalence method technology, to provide cross-checking and traceability. Baseline levels can be compared to operational air pollution profiles, and the AQMesh ultrasonic wind sensor can be used for complex site analysis, and even as the basis for modelling. 

AQMesh has been developed to meet the challenges of long-term use in mining applications and users include the biggest names in global mining. Mining applications include copper, lithium, phosphate, nickel, cobalt, nitrates with locations from Australia to Zambia. AQMesh offers a robust, autonomous network that can be a ‘sentry’ for years, with minimal maintenance/cost. 

Air quality monitoring stations have been used by the Scottish Environment Protection Agency (SEPA) to form a new air quality monitoring network around the Mossmorran Complex near Cowdenbeath and Lochgelly, Fife.

The network of 8 AQMesh pods was deployed in addition to a fixed air quality monitoring station to help address the concerns of the local community about the impact of operational activity at ExxonMobil Chemical Limited Natural Liquids Plant and Fife Ethylene Plant in Fife, Scotland. Both plants use flaring processes to burn off excess gas, and SEPA set out a series of regulations aimed at reducing the amount – and impact – of flaring, as well as being able to provide local residents with accurate, real-time information about pollution levels in the wider community.

Commenting on using the AQMesh pods, SEPA have stated that “these analysers are easier to locate than the reference analysers due to their size and power requirements and can be installed in more accessible locations. They are useful in assessing short-term trends in pollutants; provide greater geographical coverage both up and down wind of the site; and monitor for a wider range of pollutants.”

So far, all the pods and fixed station continue to show that there have been no breaches of any air quality standards since monitoring began.

The quality of the data produced by the AQMesh pods at the Mossmorran facility has been optimised using a proprietary network calibration method known as ‘long distance scaling’, which identifies and separates hyperlocal events from individual pods in order to determine the common pollutant trends seen on each pod in the network. These data trends are then directly comparable on each pod, showing the background/baseline pollution levels across the network and can also be used to provide calibration – or scaling – factors that can be applied to each pod. The method is similar to that developed by Professor Rod Jones of the University of Cambridge, which was used for calibration and quality control of 100 AQMesh pods in the Breathe London pilot.

For more information about SEPA’s air quality monitoring network at Mossmorran, or about AQMesh, contact us today.

Requests to measure hydrogen sulphide (H2S) in ambient air at unthinkably high levels seem to be at odds with our efforts to detect and report single-figure parts per billion H2S emissions. So, why are we asked for such high ranges?

We think this may be explained by operators who are used to measuring high concentration in a gas stream – typically biogas or industrial – and then simply transferring the range across when looking at fenceline monitoring. It’s great to see the growing interest in monitoring fugitive emissions at site boundaries – including H2S – but we need to dial back the gas range expected when looking at ambient pollution.

H2S sensors for gas stream measurement are offered at parts per million ranges from 0-50ppm to 0-10,000ppm. Bear in mind that US Department of Labor guidelines say that H2S odour becomes offensive at only 3-5ppm, with prolonged exposure causing headaches, nausea and insomnia, and causes “nearly instant death” at 1,000-2,000pm. Dilution of any emission in swirling ambient air means that parts per million measurements are inappropriate, and even significant H2S leaks usually register peaks of just a few parts per billion by the time gas has reached the fence line.

That’s why the AQMesh sensor measures from 0-10,000ppb (0-10ppm), with a limit of detection of less than 1ppb. Measuring at such low levels means operators can pick up emissions much earlier and much further away from the source than would be the case with the higher range sensor typically used for measuring the gas stream. Picking up a low level at a suitable point on the industrial boundary should avoid dangerous levels of H2S building up near the source.

Monitoring in ambient air is gentler on sensors, too, so if you are used to sensor poisoning and condensate problems, that benefit does offset the ‘needle in a haystack’ challenge of picking up fugitive H2S emissions. With the potential to move an AQMesh pod from location to location, and add a wind speed and direction sensor to help with source apportionment, it is very satisfying to support our users doing just that.

Each time we think we have found a spectacularly remote air quality monitoring location, an even more inaccessible spot is reported by one of our users.

Full-day trips to visit a location have now been beaten by customers who need to charter a plane to reach them. So, remote diagnostics and support are very important.

Luckily, IoT communications, cloud data management and over 10 years of experience supporting AQMesh have allowed us to continually improve our ability to supply and support AQMesh in remote locations. Pods have been used from the edges of the arctic to undeveloped deserts – as well as on ships – with the help of a few features.

Robust design, low maintenance intervals

AQMesh was designed to be rugged, for use all over the world and with an expected maintenance interval of two years. We have always understood that field maintenance requirements must be kept to a minimum, and pods operating for year after year, in the harshest environments – from deserts to extreme cold – demonstrate design effectiveness. This includes protecting electronics from the elements and mitigating electromagnetic interferences, as well as taking measures to keep insects, wildlife and birds out/off.  The unobtrusive pod design has also ensured a very low rate of vandalism and theft.

QA flags and notifications

The AQMesh data stream includes vital pieces of information which allow users and the AQMesh support team to check that pods are functioning correctly and provide an early warning system. Users can register for email notifications for their pods – it is always better to find out that power is running low or data is no longer being transmitted at the time, rather than when the project ends and it’s time to review data.

Remote scaling / calibration

Whilst AQMesh was a leader in co-location comparison and the ‘gold pod’ technique for in-field calibration, these approaches do require regular site visits to move pods around. We have now developed a method that can provide remote calibration of a sensor network, with or without an available reference station, that does not rely on artificial intelligence.

Diagnostic information

The AQMesh team can access additional diagnostic information remotely, such as performance indicators from the optical particle counter, solar pack battery voltage or sensor failures. Some of these indicators are available to users via their secure online or API access, and some can be used by our global technical support team. The team uses the full range of diagnostic information available, including SIM connection attempts, to provide free support for the life of the equipment. Their over-riding goal is to fix any problem without asking users to visit the site.

Over the wire intervention and updates

AQMesh firmware developments now allow power cycles to be triggered remotely, firmware to be updated over the wire or remote sampling and transmissions interval changed.

Power

We have learned from the many challenges that power supplies can present to remote operation. Whilst the original lithium thionyl chloride battery offered unbeaten long-term autonomous operation of gas sensors, increasing shipping limitations have turned our focus to direct power supply and solar. We invested in a full technical investigation to identify a mains to 12V DC transformer that could cope with ‘dirty’ power supplies, as well as in-pod measures to manage spiky or intermittent power.

Having seen so many problems from simple solar-panel-plus-battery arrangements, we designed our own smart solar pack, which squeezes the most power out of any location, manages power delivery and provides online voltage measurements. We are mindful that sampling and reading rates are defined by the project – and potentially certification – and the power supply must deliver the same sampling throughout the year. Readings should not be compromised by the difficulty of providing autonomous power.

Communications

The global SIM supplied with a standard AQMesh pod will roam across networks to find the best connection at each transmission, and has proven to be a very reliable way of transferring sensor output from hardware to our cloud server for over 10 years in more than 70 countries. Occasionally, we find that only a single, specific network is available – or a customer would prefer to use their own SIM – in which case we can programme the pod to work with a locally-sourced SIM contract. To achieve autonomous communication, the AQMesh LTE CAT M1 modem uses the latest LTE communications standard, including support for NB-IoT where available. In the most extreme cases, satellite communication is the only viable option and AQMesh can connect via an ethernet port to a suitable modem to connect this way. Reliable communications are key to remote data access and support.

The growing need for remote, long-term monitoring, in all conditions, drives our continuous development from data QA to comms, and we welcome challenges.

We are often asked by customers whether AQMesh air quality monitors can operate in cold conditions. Long-term use at temperatures well below freezing, with ice and snowfall, is indeed challenging.

Cold weather operation has been key to AQMesh – improved upon and proven in the field – for over 10 years. The main features, described below, have been most recently been put to the test in Iceland.

Ölfus, a municipality in Iceland, installed a number of AQMesh pods during December to measure local air quality across the town in relation to the region’s volcanic activity. The pods – supported by Vista, AQMesh distributor for Iceland – will monitor NO, NO2, CO, H2S, SO2 and particulate matter and report the data to the local Environment Agency.

A monitoring network has also been recently installed on a construction site in Reykjavík, measuring dust (PM), NO, NO2, NOx and wind speed and direction, powered by the smart solar pack. AQMesh was chosen because of successful performance in previous deployments in Iceland, as well as ease of installation and minimal maintenance requirements.

The successful operation of AQMesh pods in extremely cold temperatures can be attributed two main factors: power management and weatherproof design.

Power management

Many small sensor air quality monitoring systems use lithium batteries, which carry a recommendation for use only down to 15°C. Lithium ion batteries should not be charged below 0°C – there are risks in trying to do so – and performance is also significantly poorer at low temperatures. This is because lithium ions can plate the anode surface in freezing conditions, reducing battery capacity and increasing resistance.

The AQMesh solar pack uses the heavier but more practical 22Ah lead acid battery, which performs reliably in such temperatures. The AQMesh battery has 264Wh capacity, compared to lithium-based systems which store less than 100Wh solar power. With the battery built into the smart solar pack, capable of powering the pod for 1.5 to 2 weeks without sunlight, the pod can be powered at full capacity over the whole year at surprisingly high and low latitudes. This is particularly significant for relatively power-hungry sampling of PM: AQMesh will continue to sample at the optimal rate and not reduce sampling, which would deviate from MCERTS test conditions, voiding certification. Lead acid batteries are also easier to ship than lithium: a major consideration if you are moving pods around the UK or internationally.

Weatherproof design

Simple design considerations can be vital. Right from the first deployments across North America and Scandinavia, AQMesh design has shown that equipment cannot just survive but provide full functionality through a harsh winter, without maintenance visits. The shape of the pods prevents water, ice and snow building up on the surface, and there are no moving parts that can be affected by freezing temperatures. The AQMesh wind speed and direction sensor option is an ultrasonic anemometer, with no moving parts to wear or recalibrate, making it reliable and low maintenance.

AQMesh pods use a pump for drawing in particles, as opposed to a fan. Fans are more likely to be affected by snow and ice, potentially recirculating the same air if even partially blocked, whereas a pump will still actively draw an air sample.

Data processing on the secure AQMeshData.net server uses correction algorithms based on over 10 years of real-world testing which can compensate for extreme environmental conditions and flag affected data points if necessary.

A network of 50 AQMesh pods in Minnesota, USA, continues to operate smoothly in temperatures as low as -25°C, despite the area being under several feet of snow for long periods of the year. Other deployments include Alaska, Mongolia and Scandinavian regions, all of which experience harsh winter conditions.

For more information and to discuss your potential air quality network deployment contact our experienced team today.

If you are responsible for air pollution around an oil, gas or industrial site, you have a range of monitoring options at different price points.

AQMesh offers a cost-effective way to continuously monitor ambient air quality, as frequently as every minute, with readings accessed securely online and user-settable alerts. This system offers an ideal, confidential first step to understanding whether you – or your neighbours – have an emissions problem, particularly as the equipment is available on a rental basis, anywhere in the world.

AQMesh has been used in a wide range of applications – from the coldest to hottest conditions – for over ten years, and 15 different pollutant and environmental measurements can be provided by a single pod, using bespoke sensor configurations. The most popular measurements for petrochemical customers are hydrogen sulphide, sulphur dioxide and volatile organic compounds.

H2S, SO2 and TVOC – including EtO – can be measured down to single figure ppb, with a high level of accuracy, and CO2 readings provide a real-time, accurate measurement of local combustion. AQMesh pods can be quickly and easily deployed around petrochemical fence lines, landfill boundaries, wastewater site perimeters and around mining facilities to provide completely confidential real-time air pollution data.

One requirement we see regularly is for monitoring around vulnerable communities, such as housing areas or schools, to understand potential exposure. Pods are being used in a variety of oil & gas, manufacturing and processing applications to detect and identify sources of pollution and inform potential mitigation strategies. Although not a regulatory instrument – so readings are not generally reportable – various data management techniques can offer traceability back to an approved methodology, providing data quality assurance.

Anybody in the market for purchasing a small sensor air pollution monitoring system will need to consider budgets, but it’s not always obvious how the products being reviewed actually compare across their full operational life.

A small sensor air quality monitoring system or network can be a significant purchase, so whether project-based or with ongoing monitoring in mind, it is likely that the equipment will be in use for several years. There are six main areas of cost highlighted here, all of which kick in after initial purchase.

Without direct experience of a product, it’s natural that the focus is on the initial price tag, but that may only reveal part of the total cost. The weeks or even months spent researching products is a fraction of the time – up to 10 years – of expected product use and experience. A typical timeline of product experience will start pre-sale and run through installation, project set-up and data access arrangements, data quality assurance, planned and unplanned maintenance, co-locations and re-locations, updates, upgrades, reconfiguration, and so on. How much will you have spent – directly or indirectly – by the end of the product’s life?

Over the product’s span of operation, hidden costs can include:

1. ‘Boots on the ground’ – field staff for installation, co-location, maintenance, repairs, product replacements, and so on. Some of this will be essential, but it can add huge cost if uncontrolled, particularly if units are installed far away from the team’s base.
2. Consumables – sensors need to be replaced periodically, but how often and at what cost? Some systems require that sensors are replaced after a short time, can only be replaced as part of a multi-sensor cartridge, are very expensive, or a combination of these.
3. Data services – whilst the charge is to cover the real cost of data processing and storage (not access), annual data prices vary considerably and add up over the years.
4. SIM – an annual charge for a global SIM to connect the unit to a server is often cost-effective and convenient, but charges vary. This may depend on where in the world the unit is installed, but it’s worth checking prices and whether you have the option to use a local SIM, if that would be cheaper.
5. Support – what is included in support? Is it limited in any way? Ask for examples of committed support of networks in challenging situations, well after year one.
6. Length of warranty – this is a clear commitment from the manufacturer of what you should expect from their product: putting their money where their mouth is.

We have worked out that for two of the most popular AQMesh models (or specification) other products may be as much as 29% cheaper than AQMesh at initial purchase, but that flips to 31% to 70% more expensive overall – including the initial purchase – after five years of use. This is based on quoted consumables, data and SIM costs, so there may be even more indirect costs that we have not included in our calculation. Whilst these additional costs can possibly be accommodated within budgets for a small number of pods, hidden costs can scale at a rather alarming rate for larger networks.

It’s also worth checking how much flexibility you may have in the future:

• You may only be able to renew data services if you purchase replacement sensors
• Support may be limited in some way
• You may not be able to use a SIM of your choice

Your expectation of the product life may be different to the manufacturer’s, and that can apply in both directions. We have been asked to quote AQMesh pods, which we expect to function happily for 10 or more years, by customers who really want to buy a disposable product for a short project. If that is the case, rental is a great option. With all costs wrapped up into a single price, from three months to years at a time, costs are totally predictable and full support ensured, right through to free product replacement, should it be required.

AQMesh pods, with their robust and proven design, are expected to function in the field with minimal intervention for at least 10 years. The pods automatically come with a 5 year manufacturers’ pod warranty. We commit to – and deliver – lifetime remote support, included in the price. Remote firmware and gas processing algorithm upgrades come as part of any purchase, ensuring pods can always be updated to latest and improved versions for free.

The pods are designed to be user-serviceable, meaning only consumable components need to be replaced, rather than expensive cartridges which add cost through packaging and electronics. Consumables and yearly contracts can be purchased up front – with the initial pod order – ensuring visibility and security when it comes to future costs and maintenance, as well as appropriate discounts. Practical maintenance videos ensure that any time spent by your team is as efficient as possible, so you can plan ahead with resources and avoid unexpected demands. The team at AQMesh have been supporting pods in remote locations for over a decade, learning from our experiences along the way to ensure you get the right support exactly when you need it.

It isn’t easy to monitor air quality on or around a mining site: dusty, big machinery, water spray to suppress dust – the list goes on. But you may have to, because of a site permit or some other sort of compliance requirement. That’s the main reason we have seen, but other reasons include baselining and for health and safety.

If you have continuous dust monitoring set up, any false alarms (inaccurate high readings) can interrupt operations. Unfortunately, the very processes designed to minimise ‘high dust’ incidents can bring about just the alert being avoided: water spraying can change the characteristics of dust particles, making them bigger, looking like higher levels of dust. Such a false alarm can be avoided by heating the inlet to dry particles – but this requires higher power.

How you power air quality monitoring equipment around a mining site will depend on infrastructure and remoteness. Whilst a mains power supply is simplest, solar power offers power autonomy, even if you have to wipe the panel clear of dust occasionally. Alternatively, a 12V battery can be used. We use the mobile phone network for transmitting sensor data to the cloud, as there a very few places that don’t have some sort of mobile signal – and for the others we have satellite comms. If your site is installed with ethernet, we can power and communicate using that.

Most of our mining customers set up email alerts, so they have near real-time notice of exceedances, set to the level chosen for their site. Readings are often called by API to the client’s server or they may choose to look at latest data and trends online.

Can this sort of small sensor air monitoring equipment survive in a mining environment? The answer is a definite yes, but there will be some considerations, such as maintenance requirements and whether there are any consumables to replace.

Contact us today to chat about how AQMesh air quality monitoring systems can help support air quality monitoring strategies around your sites.

Or how many air quality measurement points do I need?

Annoying as it is, the answer is ‘it depends’. The list of factors which affects this not exhaustive but is based on our experience and we’ll try to be a bit more helpful afterwards.

• Size, location and topography of site
• Position and range of pollution sources and ‘receptors’ (such as communities or schools)
• Wind direction and strength
• Complexity of area being monitored, including multiple sources and street canyons
• Analysis capability
• Your budget!

Generally, the limiting factor will be budget. The clue is in the name with hyperlocal air quality monitoring, and pollution levels can vary hugely over short distances. NO measurements around streets, for example, are often significantly different from one side of the road to the other, particularly if there isn’t much wind and/or a street canyon effect. It is important to agree objectives and priorities in any city monitoring project, as it is simply not possible to meaningfully instrument the entire city, even with the biggest budgets. Even should budgets be effectively unlimited, the challenges of data management, quality assurance and interpretation get harder and harder the more nodes you have.

When monitoring air quality at the fence line at remote or industrial facilities, dilution of pollutants mixing with air around the site reduces the chance of a ‘spike’ being picked up from a plume, so generally the more measurement points that can be afforded, the higher the likelihood of detecting fugitive emissions, whether CO2, NOx, SO2, H2S, TVOC or particulate matter.

In either scenario, a hybrid network can help optimise the return on investment, so mixing a range of sensors with reference stations can help to fill gaps cost-effectively. The limiting factor with this is that any sensor used in the network has to provide comparable data. In theory a (very) low cost sensor could be used in high numbers to provide wide coverage, but if the cheap sensor does not have the necessary sensitivity (particularly when looking for low concentrations in a plume), data accuracy or comparability with other technologies (or even precision between themselves) in the network, there is a serious danger that project objectives will not be met and money will be wasted.

In our experience, the best way to achieve optimal coverage is the following recipe:

• At least one well-maintained reference station (if a reference station is not available, diffusion tubes/passive samplers can be used to good effect)
• As many good quality small sensor systems as you can afford
• Normally one wind speed and direction sensor per site (this may be more complex if the wind direction is obstructed by topography or buildings) or local wind data may be available
• Data analysis and quality assurance resource, with complete traceability
• Calibrate small sensors against reference
• Position small sensor systems precisely where required, free of infrastructure limitations, with autonomous power and communications
• Carry out analysis to identify sources and distinguish background from locally-generated pollution
• Stick to the sensor system manufacturer’s recommended maintenance procedures, however minimal, to ensure data reliability over the longer term
• Follow local and international advice on quality assurance of data
• Beware of big promises offered by AI – current local training of sensors comes with significant drawbacks

We are happy to provide more advice, dependent on your situation.

Our hydrogen sulphide (H2S) monitoring journey literally started in the sludge lanes of a UK wastewater treatment plant in 2017. Since then, AQMesh has been used effectively in a range of applications.

Monitoring H2S in air at levels of less than one part per billion – well below the level at which the human nose can detect this odorous and harmful gas – AQMesh can be used both to measure very dilute levels and where concentrations are significant. These small ‘pods’, with autonomous power and communications, can be quickly installed around a boundary, providing 24/7 monitoring. Near real-time readings are accessible on a laptop, phone or via alerts, indicating where H2S levels have exceeded a set threshold. This core capability has been used in various sectors.

Waste water, landfill and waste management

As H2S smells unpleasant – and may be released as a fugitive emission alongside other odorous gases, such as ammonia and mercaptans – AQMesh has been used to monitor air quality at site boundaries. The AQMesh team cooperated with a UK water utility in 2017 to prove the accuracy of the AQMesh sensor against a Honeywell SPM Flex, showing very good correlation.

During the monitoring period the AQMesh pods were moved from an outdoor monitoring location to indoor, and this saw a significant uplift in H2S levels. Across this range (0 to over 100ppb) the correlation with the Honeywell unit was very strong, at an R2 of around 0.9.

Since this original study, AQMesh has been used to monitor at landfill and waste management sites around the world, including New Zealand, Iceland, South Africa and UK. Continuous, real-time boundary measurements can be used to investigate odour nuisance complaints, with alerts set up if concentrations exceed agreed limits, over a user-set time interval. As pods are deployed closer to the source of emissions, monitoring can be used to alert operators to high levels of H2S, as well as other pollutants. Action may need to be taken, such as enclosing spaces or protecting staff from inhaling elevated levels of pollutants.

Industrial processes

Linked to H2S from waste, AQMesh is currently being used to monitor H2S levels at a site close to a biorefinery plant, where measured levels of the gas show regular peaks.

Other industrial processes where real-time H2S monitoring can add value are the oil and gas industry – particularly relating to sour, or sulphur-heavy gas, and oil sand extraction – as well as lime manufacture and paper processing. The most common air pollutants generated by the pulp and paper industry are nitrogen oxides, sulphur compounds, particulate matter (PM) and volatile organic compounds (VOCs), all of which can be monitored by a single AQMesh pod. AQMesh has been used in all these applications, providing secure, confidential, real-time information to operators, to protect staff and neighbouring communities, and identify sources, mitigating where necessary.

Ports and shipping

Shipping has long been under fire regarding the levels of sulphur in fuel, as well as other air pollutants. AQMesh has been used in various studies which have aimed to identify the sources of pollution around ports, as harbourside operations and nearby traffic movements – inside the port and on roads in the neighbouring area – also create air pollution. Capturing plumes from ships is notoriously difficult but possible, using AQMesh capturing data at 1-minute intervals and wind speed and direction (an integrated AQMesh option), analysed to identify the direction and scale of the source.

Volcanic activity

Volcanoes present another significant source of sulphurous emissions. Five AQMesh pods were installed at and near Keflavik airport in Iceland, monitoring gases produced by the nearby volcano at Fagradalsfjall, including H2S, sulphur dioxide (SO2) and nitrogen dioxide (NO2). The monitoring project was a collaboration between the airport authority, Isavia, and the Icelandic Environment Agency, to ensure good air quality for Isavia staff as well as users of the airport and local residents. Three AQMesh pods were located at Keflavik airport, with two others installed in nearby towns to monitor air quality in the local community, with measurements published on a website.

A 2017 study in Nicaragua, led by the University of Leeds, predated the AQMesh H2S sensor option, focusing on SO2 and particulate matter. The pods, with independent power and communication, were set up to understand how it might be possible to provide early warning to residents of dangerous levels of SO2 and PM.

Monitoring hydrogen sulphides to prevent short-circuits at data centres

H2S in the air – which can come from a number of sources – is a particular risk to information technology, as it can damage copper circuitry. Airborne H2S and SO2 can form a weak acid, which can cause dendrites to form on electronic components, resulting in short-circuits and potential data loss. This risk is growing worldwide, with more compact circuitry increasing the risk of short-circuits, and more data centres being located in areas with higher levels of H2S and SO2 in the air.

H2S attacks copper, forming thin films of metallic sulphides – dendrite whiskers – which speed up corrosion, so some data centre operators monitor H2S outdoors, near air intakes, and internally within UPS rooms to avoid sulphur-induced degradation in power modules. These gaseous contaminants can lead to deterioration of silver solder as well as copper surfaces on computer circuit boards, leading to intermittent and hard errors, caused by either impeding the flow of electricity or forming unintended circuit paths.

Data centres focus on filtration for particles and management of temperature and humidity, but gases in the air may bypass such filtration systems. One method of monitoring for potential corrosion is to expose silver and copper coupons to the air in the server centre and measure corrosion over a month. This is an effective methodology, but the results of the month-long test may arrive too late to prevent damage. Monitoring of the air coming into the building allows real-time notification of elevated levels of H2S and SO2, allowing action to be taken before polluted air enters the data centre.