Monitoring agencies are required to conduct a network assessment once every 5 years [40 CFR part 58.10(d)EXIT].  The primary objectives of the Network Asessments is to determine if the network meets the monitoring objectives defined in appendix D to this part, whether new sites are needed, whether existing sites are no longer needed and can be terminated, and whether new technologies are appropriate for incorporation into the ambient air monitoring network.

This page contains links to guidance documents intended to assist monitoring agencies conduct these required network assessments.  In addition to these guidance documents, EPA has updated the Network Assessment Tool originally created by the Lake Michigan Air Directors Consortium (LADCO).  That tool can be accessed at this site - https://sti-r-shiny.shinyapps.io/EPA_Network_Assessment/ Exit

• Ambient Air Monitoring Network Assessment Guidance (PDF)(72 pp, 2 MB)
  Analytical techniques for technical assessments of ambient air monitoring networks
• Designing a Network Assessment for an Ambient Air Monitoring Program (PDF)(29 pp, 403 K)
  Frequently asked questions and checklists to assist monitoring agencies prepare for and execute a network assessment