Ambient Air Quality Monitoring

• It identifies faulty practices within institutions and helps implement robust monitoring systems to measure the set target for pollution reduction and achieve clean air. 
• Helps monitor improvement, degradation, or any change in air quality.
• Informs people about environmental conditions and is helpful for people suffering from diseases caused by air pollution.
• It helps people compare air conditions from different locations.

Why do we need Air Quality Monitoring?

• Monitoring pollutant concentrations serves as the basis of pollution abatement strategies. The primary purpose of monitoring is to determine essential insights and relevant information that helps us define the pollution problem to solve it. Air quality monitors also enable us to track the progress of mitigation strategies by assessing the efficacy and efficiency of policy intervention. With such data, we can fine-tune our response to reduce exposure to harmful pollutants in our surroundings.
• The principal factors governing air pollution are, the location of the source of emission (indoor and outdoor), topography, and meteorological conditions. Due to region-specific factors and varied climatic conditions, the distribution and extent of pollution is different everywhere. 
• According to the US EPA, it is imperative to monitor the pollution problem of the region of interest to reduce the concentration levels. Following are the reasons why we need to monitor ambient air quality:

Parameters that are measured in air quality monitoring

At the federal level in the United States, the USEPA measures six criteria pollutants under the NAAQS:

• Ground-level ozone
• Particulate matter
• Carbon monoxide
• Lead
• Sulphur dioxide
• Nitrogen dioxide

Indoor air quality monitoring Vs Outdoor Air Quality Monitoring:

indoor air quality commonly known as IAQ refers to the air quality within and around buildings and structures, especially as it relates to the health and comfort of building occupants. Understanding and controlling common pollutants indoors can help reduce your risk of illnesses caused due exposure to poor indoor air quality. 

The air in indoor spaces is as polluted as, if not more than, outdoor air. The components of indoor air are particles such as dust mites, pollens, carbon fibers, pet dander, etc., and Odors such as VOCs (Volatile Organic Compounds) from paints and varnishes, smoke, cooking Odors, etc. We overlook the rudimentary inclusions at home that contribute the most to polluting indoor air quality. The effects of indoor air pollution are so severe that they impact our productivity at work, children tend to feel lethargic within a period after being exposed to polluted air for a long time, which may lead to absenteeism, and a greater impact on education can be observed perhaps.

Whereas, Outdoor air quality monitoring or Ambient air quality refers to the air quality outside and often inside certain premises and is referred to as ambient air quality. Ambient air quality standards are laid by different organizations that define the concentration of pollutants in the air to promote a better and healthy way of living for human beings, and animals and also for the welfare of the environment. 

Ambient air pollution is driven by industrialization, uncontrolled urbanization, population growth, fossil fuel combustion, and an absence of adequate national or international chemical policy. Ambient air pollution levels are on a constant rise with around 66% of increment over the past two decades. Policies like the Green Belt can be very effective in naturally improving air quality. Green belt safeguards the vital resources that clean our air by capturing particulate matter and gradually enhancing the quality of air.

Methods of Monitoring Air Quality - How is Air Quality Measured?

TEOM: 

Tapered Element Oscillating microbalance analyses the concentration of particulate pollutants by passing the air through an exchangeable filter cartridge leading to the deposition of particulates on the filter. The filtered air then passes through the tapered tube to a flow controller. This air monitoring equipment is used to analyses particles less than equal to 10 micrometres in diameter. 

Beta Attenuation Monitoring (BAM): 

This is the conventional technique for ambient air quality monitoring PM10 and PM2.5 pollutants. This method of outdoor air quality monitoring employs the absorption of beta radiation by solid particles extracted from airflow.

What are AAQMs and CAAQMs?

 Ambient Air Quality Monitoring Systems (AAQMS):

Ambient air quality monitoring systems or generally known as Manual air quality monitoring systems sample ambient air and collect the data for a period of time to then manually transfer the data for analysis. Once the data is analysed, a report is prepared manually.  AAQMS includes a High-Volume Sampler System to sample a known volume of air through the use of filters. Depending upon the weight before and after sampling, the filter is analysed for different pollutants. The process of air sampling, data collection, data analysis, and report preparation take from 2 to 7 days to provide the proper information about ambient air pollution in a particular location. 

Continuous Ambient Air Quality Monitoring Stations (CAAQMS):

Continuous Ambient Air Quality Monitoring Stations use exclusive technology like IoT to collect and transfer data automatically with reduced chances of manual errors. It is an advanced version of AAQMS. The air quality data is collected in real-time and transferred to the servers for analysis and preparation of reports. The interval of transfer of data is adjustable between 2-30 minutes and then the data is analysed with AI and used accordingly. 

CAAQMS works on different principles and analysers in an automated manner, generating accurate data, and reducing the possibility of manual errors. There are two ways to analysed data for continuous ambient air quality monitoring.