|제목||Air quality monitoring sensors: importance, emerging trends and challenges (A.....|
Air quality impacts human health. Period.
Heart disease, lung disease, stroke, and increased mortality rates have been definitively linked to air quality, specifically the concentrations of particulate matter (PM 2.5) and other criteria pollutants (Taylor, 2016). The World Health Organization (WHO) estimates that outdoor air pollution is responsible for approximately 4.2 million premature deaths per year. It is also estimated that over 90% of the world’s population live in places where air pollution levels exceed WHO standards.
People have noticed.
These statistics have increased investment in air monitoring programs and mitigation plans. In 2017, California passed Assembly Bill 617 with the intent to use air quality monitoring technology to increase data and develop community-scale emissions abatement programs. But there are costs associated with these goals.
The machines that are used by governments right now to do air quality monitoring cost thousands of dollars to purchase, not to mention require trained resources to maintain and record data outputs. Luckily, as technology has been evolving, more and more low cost sensors are becoming available in the market place.
Low costs sensors: cost vs. accuracy
There are low cost sensors designed to monitor air quality for individuals, homes, businesses, and neighborhoods. While the individual sensors are usually only capable of monitoring one type of pollutant, there are sensors available for particulate matter, nitrogen dioxide, ozone, carbon monoxide, and volatile organic compounds (VOCs).
It is expected that in the future, air quality data will be coming from a variety of sources, rather than just from government monitoring. The benefit of this is having big data available to track large scale trends and perform other complex analyses. However, the data quality of low cost sensors varies greatly. The effectiveness and accuracy of the many low cost sensors is unknown because they are not currently held to any national standards.
While the EPA is closely monitoring the market, they do not have the resources to keep up with number of products being released. In the future, it is possible that a market for third party sensor assessment may emerge.
What do the numbers mean?
There are two challenges with the data coming from low cost sensors, the first being accuracy and the second being the ability of users to interpret the data. A person with no background in air quality can read the number, but without context has little ability to understand what the number means, if it is good or bad, or what other potential contributing factors exist.
Durability, longevity, sustainability
Performance of any air quality sensors can be impacted by weather conditions such as heat, humidity, and extreme cold which all impact data quality. Sensor drift is also a well-known phenomenon that is regulated and remedied by regular calibrations. Some of the new low cost sensors cannot be calibrated and are effectively disposable, having a recommended expiration date.
The future of air quality monitoring
The fact is that low cost air quality sensors, and highly accurate, regulated sensors both have a place in the future of air monitoring. There are positives and negatives associated with both but they both play a different, and increasingly important role in our collective venture to ensure air is safe to breathe for everyone.