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Nothing is more fundamental to life than air quality. In a lifetime, about 300 million liters of air pass through the average person’s lungs. If that person walks along a busy city street today, he will inhale around 20 million particles with each lungful.
Scientists were aware of the impact of air pollution as far back as the seventeenth century. Now, as more of us live in cities, we are closer than ever to pollution sources, and their detrimental impact on the environment and our health has reached a crisis point.

Toxic air is now a significant environmental risk for every sector. As its impact has seeped into everyday life, it is no longer just a concern for heavy industry. It affects commuters, vehicles, and equipment too, so it is unsurprising that governments around the world are introducing increasingly strict legislation on tackling air pollution to protect their citizens.

Air quality has become a legislative concern, bringing the issue into sharp focus for a range of industries. The most damaging but best-understood pollutants are tiny particles of black carbon, nitrates, sulfates, ammonia, or mineral dust. Often produced by power plants and heavy industries, these pollutants can, in effect, cannibalize the equipment and workers used in these industries.

It is now generally understood that these particles will not only damage the lungs but enter the bloodstream. From there, they can increase the risk of a wide number of health conditions, meaning businesses have a moral imperative to monitor the air quality on their sites and protect the people who work there.

Uncontrolled air quality can lead to other, more immediate health risks. Some environments may see high concentrations of toxic gases, such as carbon monoxide, in the air, which pose a more immediate risk to work safety. Other pollutants may present an explosion risk or cause corrosion to equipment which presents a significant risk of asset damage in addition to health and safety concerns.

Between the increased risk to workers, machinery, and other assets, and the rapidly shifting legislative landscape, the business case for improving air quality is now open-and-shut. Before this can happen, however, the state of the air must be more closely monitored.

Monitoring emissions from stationary sources of pollution, such as power stations, manufacturing plants, and other industrial facilities, is essential for a whole host of reasons. Industry accounts for over 24 % of global greenhouse gas emissions, so ascertaining the concentration of various gasses emitted and subsequently allowing relevant authorities to check whether the site is complying with its legal obligations remains essential. For example, efforts to reduce methane emissions could yield a rapid decline in the rate of global warming.
Leakage and venting from the energy sector remain significant sources of harmful emissions, but our gas detection filters continue to contribute to a real-world solution. The science is unequivocal: we are going in the wrong direction.
A considerable portion of climate change or global warming can be attributed to our reliance on industrial activities. It has been claimed that factories are to blame for up to two-thirds of the pollution that has caused climate change.

The problem requires determined political engagement and action at a local and national level, but action is required to ensure it remains a priority. Thanks to campaigns, the growing availability of low-cost air-quality monitors and increased awareness of local air quality could help to change that.

Proper communication with the business community has also been sorely lacking. Market leaders want information on how and what they can do about it. Any new air quality information system needs to be based on what people are exposed to in their localities, including real-time variations.

Industrial plant owners who must abide by specific regulatory frameworks invest in measuring equipment to report what and how much is coming out of the stack.

In the market for measuring emissions, there are many measuring technologies. The logical first step toward resolving this air crisis would be to make much more real-time air quality data available to the public and increase air quality data transparency, as well as initiatives to educate people on the long-term consequences of breathing in polluted air. People can take various precautions to safeguard themselves and others if they know the severity of the pollution they are inhaling.

There are two broad categories of gas detectors: point detectors and area detectors. IR gas detectors compare the amount of light at a specific wavelength where Hydrocarbon molecules absorb light (the sample) with light at a wavelength where no absorption occurs (the reference). When the light passes through a hydrocarbon gas, the intensity at the sample wavelength will drop, while the intensity at the reference wavelength will be unaffected. The ratio of the two signals is proportional to the gas concentration.

An IR detector consists of one or more infrared sources, one or more infrared detectors and precision optical filters to separate the sample and reference wavelengths from the background light. It also requires a light path open to the atmosphere so gas can diffuse into the light beam.

Due to the dependence of the absorbance on the wavenumber, different gas components can be distinguished using the absorption spectrum.

Gas detection systems have been deployed extensively in the process industry to detect and mitigate gas releases and minimize their potential consequences. Detection mechanisms differ between chemicals, and consideration must be given to selecting the right technology for each application, along with practical installation, commissioning, and maintenance considerations.

Most current applications trigger an alarm for the operator based on high readings from gas detectors. However, with the industry push to incorporate safety gas sensors into shutdown systems, the need to design, calibrate and commission these sensors correctly to reduce nuisance trips is increasingly essential.

Did you know?

Point gas detectors have a single detector location requiring the gas cloud to interact with the sensor.

Point detector types include catalytic, electrochemical, solid state, and infrared (IR). An IR detector consists of one or more infrared sources.

Text: Mark Naples Umicore Coatings Services