Our website provides a free download of EPA PMF 5.0.14. Our built-in antivirus scanned this download and rated it as 100% safe. The actual developer of the free software is U.S. Environmental Protection Agency. The software is included in Education Tools.
From the developer:
EPA’s Positive Matrix Factorization (PMF) Model is a mathematical receptor model that provides scientific support for air and water quality standards, exposure research, and a wide range of environmental data analyses from PCB contaminated sediments to indoor air quality.
You may want to check out more software, such as EPA Metadata Editor, EPA Unmix or EPA SWMM, which might be related to EPA PMF.