Low-Cost Air Quality Monitoring Systems

Today’s environmental information systems combine the newest sensor and monitor technologies with the data transfer; database developments, quality assurance, statistical and numerical models, and advanced computer platforms for processing, distribution, and presenting data and model results. Geographical Information Systems (GIS) are a crucial tool, particularly for the presentation of knowledge. A crucial part of the integrated air quality management system is the establishment of a monitoring program for air quality. Once the target of the air monitoring program is well-defined, a finicky operational sequence has to be followed. The simplest possibility of the pollution problem, alongside the analysis of the personnel, budget, and equipment available, represents the idea for the ultimate design. The specification of monitoring objectives, data quality objectives alongside proper site selection, data quality assurance, and well-defined data presentation and assessment are important elements during this process.

 Air Quality Monitor

Air quality monitor is a device that measures the degree of common air pollutants. Monitors are presented for both indoor and outdoor settings. Indoor air quality monitors are typically sensor-based instruments. A number of them are ready to measure ppb levels and are available as either mixed gas or portable units. Sensor-based instruments and air quality monitoring systems are used extensively in outdoor ambient applications.

Air Quality Monitoring Network Design

The design of the air quality monitoring network involves determining the integer of stations and their location, and monitoring methods, with an observation of the objectives, costs, and available resources. The standard approach to the network design, appropriate over the city-wide or national scale, involves placing monitoring stations or sampling points at carefully selected representative locations, chosen on the idea of required data, and known emission/dispersion patterns of the pollutants under study. The scientific approach will produce a price effective air quality monitoring program. Sites should be carefully selected if measured data is to be assumed useful. Moreover, modelling and other objective assessment techniques may have to be utilized to fill within the gaps of any such monitoring strategy.

Monitoring Objectives

The air quality monitoring program design is going to be dependent upon the monitoring specific objectives specified for the air quality management within the selected area of interest. Defining the output will influence the planning of the network and optimize the resources used for monitoring. There happen to be different objectives for the event of environmental monitoring and closed-circuit television.

Normally, the system will need to provide online data and knowledge transfer with immediate internal control of the collected data. Several monitors, sensors, and data collection systems could also be applied to form online data transfer and control possible.

The objectives stated for the occurrence of an air quality measurement and surveillance plan could be to:

  • facilitate the backdrop concentration dimensions
  • monitor present levels as a baseline for assessment
  • check the air quality relative to standards or limit values
  • perceive the magnitude of individual sources
  • enable contrast of the air quality data from different areas and countries
  • procure data for air quality management, traffic, and land-use planning purposes, − observe trends
  • build up abatement strategies
  • establish the coverage and assess the cost of pollution on health, vegetation or building materials
  •  inform the community about the air quality and raise the notice[i]

Connection of Air (Prevention and Control of Pollution) Act 1981

Government of India enacted the Air (Prevention and Control of Pollution) Act 1981 to arrest the deterioration within air quality and also suspends the power on the board. The act mainly prescribes the various functions and powers for the Central Pollution control panel at the apex level and State Pollution control panel at the state level. 

Functions of Central Pollution control are as follows:

  • To direct the Central Government on any matter regarding the growth of the standard of the air, and therefore, the prevention, control, and abatement of pollution.
  •  To prepare and cause to be executed a nation-wide program for the avoidance, organize, and abatement of pollution.
  • To provide technical assistance and direction to the State Pollution control panel.
  • To hold out and support investigations and investigate connected with pollution prevention, control, and abatement of pollution.
  • To gather, compile, and publish technical and statistical data associated with air pollution; and
  • To get down standards for the standard of air and emission quantities.

Functions of the State Pollution control are as follows:

  • To plan a comprehensive program for avoidance, power or abatement of pollution and to secure the execution thereof;
  • To recommend the government on any matter concerning prevention, control, and abatement of pollution.
  • To congregate and broadcast information associated with pollution.
  •  To collaborate with Central Pollution control panel in the program associated with prevention, control, and abatement of pollution; and
  • to examine air pollution control areas[ii].

Effect of National Ambient Air Quality Standards (NAAQS)

The ambient air quality objectives/standards are prerequisites for developing a management program for effective management of ambient air quality and to scale back the damaging effects of pollution.

The objectives of air quality standards are-

  • To submit the quantity of air quality essential with an adequate margin of safety to guard the public health, vegetation, and property.
  • to assist in establishing priorities for abatement and manage of pollutant echelon
  •  to provide a uniform yardstick for assessing air quality at the national level
  • to point the necessity and extent of the monitoring program

Therefore, the Central Pollution control panel had adopted first Ambient Air Quality Standards on Veterans Day, 1982 as per section 16 (2) (h) of the Air (Prevention and Control of Pollution) Act, 1981. The air quality standards are revised by the Central Pollution control panel on April 11, 1994. The National Ambient Air Quality Standards were revised and depicted. These standards are supported the land use and other factors of the world.

The rules for declaring sensitive areas as recommended by peer/core group of C.P.C.B. are as follows

  1.  10 km all around the periphery of health resorts so notified by State Pollution Control Boards in consultation with the department of public health of the concerned state.
  2. 10 km all around the periphery of biosphere reserves, sanctifies, and national parks, so notified by the Ministry of Environment, and Forest or concerned states.
  3.  5 km all around the periphery of an archaeological monument declared to be of national importance or otherwise so notified A.S.I. in consultation with State Pollution Control Boards. 
  4. Areas where some delicate or sensitive to pollution crops/important to the agriculture/horticulture of that area is grown so notified by State Pollution Control Boards in consultation with the department of agriculture/horticulture of concerned state[iii].

Air Quality Monitoring Ambient air quality monitoring is required to work out the prevailing quality of air, evaluation of the effectiveness of the control program, and to spot areas in need of restoration and their prioritization. National Air Quality Monitoring Programme is described during this chapter along with details on pollutants measured and their frequency.

National Air Quality Monitoring Programme (N.A.M.P)

Central Pollution control panel initiated the National Ambient Air Quality Monitoring (NAAQM) program within the year 1984 with 7 stations at Agra and Anpara. Subsequently, the program was reiterated as National Air Monitoring Programme (N.A.M.P.). The amount of monitoring stations under N.A.M.P. has steadily increased, to 308 operating stations.


The objectives of the N.A.M.P. areas firstly to work out status and trends of ambient air quality, to determine whether the prescribed ambient air quality standards are violated, to spot non-attainment Cities where air pollutants are exceeded prescribed standards, to get the knowledge and understanding necessary for developing preventive and corrective measures and to know the natural cleansing process undergoing within the environment through dilution, dispersion, wind-based movement, dry deposition, and chemical transformation of pollutants generated.

Monitoring Locations and Parameters Under N.A.M.P

Four main air pollutants that are sulfur dioxide, Oxides of Nitrogen,  Suspended particulate and Respirable Suspended particulate (RSPM/PM10), are identified for normal monitoring in the least the locations.

Besides this, additional parameters like Respirable Lead and other toxic trace metals, Hydrogen Sulphide, Ammonia, and Polycyclic Aromatic Hydrocarbons also are being 4 monitored in 10 metro cities of the country. The monitoring of meteorological parameters like wind speed and direction, ratio, and the temperature was also integrated with the monitoring of air quality. The monitoring of pollutants is administered for twenty-four hours with a frequency of twice every week, to possess 104 observations during a year[iv].

CPCB co-ordinates with agencies which are connected with NAMP to make sure the uniformity, consistency of air quality data and provides technical and support to them for operating the monitoring stations. Since the target sampling of 24 hours during a day couldn’t be fulfilled in the least the locations thanks to power failures etc., the values monitored for 16 hours and more are considered as representative values for assessing the ambient air quality for each day. 

The target frequency of monitoring twice every week, 104 days during a year couldn’t be met in a number of the locations, in such cases 40 and more days of monitoring during a year is taken into account adequate for the aim of knowledge analysis. N.A.M.P. is being operated through various monitoring agencies, a sizable amount of personnel and equipment are involved within the sampling, chemical analyses, data reporting, etc. It increases the probability of variation and personnel biases reflecting within the data, hence it’s pertinent to say that these data be treated as indicative instead of absolute.

Quality control of air quality monitoring for credible and reliable data internal control for credible and reliable data is of utmost importance. this can include quality assurance program for comparability of knowledge from various agencies; quality assurance in laboratory – periodic calibrations, duplicate checks, split samples, spiked samples and therefore the keeping of adequate and neat records; on-site system surveys, independent performance audits, inter-laboratory comparisons and periodic evaluation of internal quality assurance data, etc; data handling and presentation; calibration and auditing of equipment and training, infrastructure, skill-building, power supply, etc.

CPCB has urbanized a protocol for the quality pledge. Scheme and instrument audits for operation and performance are going to be critical. Experience in developing country cities show the gamut of challenges which includes lack of certification of monitoring instruments, lack of standardized methods for calibration, high error levels, poor comparability and repeatability of results, high variability in results aren’t checked, little control over monitoring environmental conditions, lack of spare parts and stand by equipment, and even erratic power supply. Out of these, there exists need to be addressed and prevented while developing the protocol for monitoring. Quality operation practices are defined by CPCB. This may need to focus on data quality, measurement methods, site selection, instrumentation, network design and site of monitoring, data validation, and capacity building. Adequate size and scope of air quality monitoring system supported population and area size.

Manual versus automatic monitoring

Automatic analyzers are often to monitor all gases and particulate of all size fractions. These are sophisticated analyzers with good internal control and assurance. Instant online real-time data generation and dissemination take place helping in air quality index and early warning system and forecasting and modelling. Just in case of manual monitoring PM10 and PM2.5 and most gases in particulate are often monitored. In the gravimetric method, sample processing is completed by chemical analyzers and for gases, wet analyzers are used.

However, challenges concerning quality assurance and internal control remain in manual monitoring like delayed reporting and no instant replay of knowledge. Delhi relays real-time air quality data. This is often user friendly. One can access the station wise continuous real-time hourly update or 24-hour average data. Back data is additionally available. But there are maintenance issues. Link air quality monitoring with routine public data system CPCB has adopted an air quality index system, a globally established tool to classify the air quality in several categories supported the severity of the matter.


Air quality monitoring systems are designed using different sensors for indoor and outdoor air quality monitoring within the previous works by using Bluetooth, GPS, and GPRS wireless technologies. The proposed system is developed for indoor air quality monitoring remotely. It’s cost and energy-efficient request and response protocol is employed along with side combination of address and data-centric protocols.


  • What does Air Quality Monitor mean?
  • How Air Quality Monitor is networked?
  • What are the Objectives of Monitoring?
  • Who hold powers of arrest for air pollution?
  • Who is responsible for Air Quality Monitoring?
  • Whether Manual Monitoring or Automatic Monitoring?

[i] http://www.indiaenvironmentportal.org.in/files/airquality17cities.pdf


[iii] https://link.springer.com/chapter/10.1007/978-3-319-61346-8_25

[iv] https://scclmines.com/env/DOCS/NAAQS-2009.pdf

Leave a Reply

Your email address will not be published. Required fields are marked *