The Field Audit Checklist Tool (FACT) is a Windows desktop application intended to help auditors perform field audits of facilities that report data pursuant to the continuous air monitoring requirements of the Clean Air Act (40 CFR Part 75). FACT allows users to easily view monitoring plan, quality assurance and emissions data. FACT also provides access to data collected under the Mercury and Air Toxics Standards (MATS). FACT uses web services to display data via an Application Programming Interface (API). An API is a set of commands, functions, protocols, and objects that programmers can use to create software or interact with an external system. An API interprets that data and presents you with the information you wanted in a readable way.