How do you design an air quality monitoring network?

1 Define the purpose

The first step in designing an air quality monitoring network is to define the purpose and scope of the network. What are the main questions or problems that the network aims to address? Who are the intended users and stakeholders of the network? What are the legal or regulatory requirements that the network must comply with? How will the network data be used for air quality management and decision making? These questions will help you to identify the specific objectives and criteria that will guide the network design.

2 Select the pollutants and parameters

The next step is to select the pollutants and parameters that the network will measure. This depends on the purpose of the network, the sources and characteristics of the pollution, and the availability and suitability of the monitoring methods and equipment. Some of the common pollutants and parameters that are measured in air quality monitoring networks include particulate matter (PM), nitrogen oxides (NOx), sulfur dioxide (SO2), ozone (O3), carbon monoxide (CO), volatile organic compounds (VOCs), meteorological variables, and traffic counts. You should also consider the spatial and temporal resolution, accuracy, precision, and quality assurance of the measurements.

3 Determine the network size and location

When determining the network size and location, it is important to consider the spatial variability and distribution of the pollution, the representativeness of the monitoring stations, the accessibility and security of the sites, and any potential interferences or biases from nearby sources. Additionally, you should take into account power, communication, and maintenance facilities. To optimize the network size and location, there are various methods and tools available, such as statistical analysis, geostatistical modeling, spatial interpolation, multi-criteria evaluation, and sensitivity analysis. Balancing the trade-offs between cost, benefit, and uncertainty is a complex and challenging task.

4 Choose the monitoring equipment and methods

When choosing the monitoring equipment and methods to measure the selected pollutants and parameters, you should take into account the performance, reliability, and affordability of the equipment and methods, as well as the operational and maintenance requirements. Factors to consider include the measurement principle and technique, detection limit and range, response time and frequency, calibration and validation procedures, data acquisition and transmission systems, power consumption and supply, environmental conditions, and protection. There are various types of monitoring equipment and methods available, such as continuous analyzers, passive samplers, optical sensors, remote sensing, and mobile monitoring.

5 Implement and operate the network

The fifth step is to implement and operate the network, which involves installing, testing, and running the monitoring equipment and methods at the selected sites. This requires careful coordination, supervision, and documentation of the network activities, as well as regular inspection, calibration, and maintenance of the equipment and methods. When doing so, you should take into account factors such as installation and commissioning protocols, operation and maintenance manuals, quality control and quality assurance plans, data management and reporting systems, health and safety measures, contingency and emergency plans, and training and capacity building programs. Additionally, it is important to establish effective communication with network partners, users, stakeholders, in order to seek feedback and evaluate the network performance and outcomes.

6 Review and improve the network

The sixth and final step is to review and improve the network, which involves assessing and updating the network design and operation based on the network data and feedback. This is an ongoing process, as the network should be able to adapt to changing needs and conditions of air quality management and decision making. When reviewing and improving the network, you should consider the objectives and criteria, data quality and usability, costs and benefits, gaps and limitations, opportunities and challenges, as well as innovations and best practices. Additionally, it's important to monitor and report impacts and achievements, share lessons, and disseminate experiences.