These files document all analyses conducted in association with the EPA memorandum from Terence Fitz-Simons, Scott Mathias, and Mike Rizzo titled "Analyses of 1999 PM Data for the PM NAAQS Review," November 17, 2000. These analyses were conducted for the review of the Particulate Matter (PM) national ambient air quality standards (NAAQS). Both 1999 PM10 and PM2.5 data were extracted from EPA's Atmospheric Information Retrieval System (AIRS) data base on various dates in July, 2000. Each analysis is documented in a separate attachment to this memorandum. The following zipped files are available for downloading:

• Memo: Analyses of 1999 PM Data for the PM NAAQS Review(3 pp, 20 K, 11/17/2000)  
• Attachment A: 1999 PM Data Description (provides important information on the PM data used in all analyses, including how certain data validation flags were handled)(1 pg, 129 K, 11/17/2000)
• Attachment B: 1999 PM2.5 Annual Mean and 98th Percentile 24-Hour Average Concentrations(1 pg, 572 K, 11/17/2000)
• Attachment C: 1999 PM10 Annual Mean and 2nd Highest 24-Hour Average Concentrations(1 pg, 765 K, 11/17/2000)
• Attachment D: 1999 PM(10-2.5) Annual Average and 98th Percentile 24-Hour Average Concentrations(1 pg, 286 K, 11/17/2000)
• Attachment E: 1999 Ratio of PM2.5 to PM10 Concentrations for Co-located Monitors(1 pg, 111 K, 11/17/2000)
• Attachment F: Spatial Variability of PM2.5 and Other Pollutants(1 pg, 288 K, 11/17/2000)
• Attachment G: Local-Scale Spatial Variability of PM2.5 Concentrations for Selected Metropolitan Areas(1 pg, 438 K, 11/17/2000)
• Attachments H-J: Correlation of PM2.5 and PM10 to Other Pollutants; Correlations Between 24-Hour Average PM2.5, PM10, and PM(10-2.5) Concentrations; PM2.5 Correlation Matrix for Specified Metropolitan Areas(1 pg, 106 K, 11/17/2000)
• Attachment K: Distribution of Monthly Average PM2.5 Concentrations by MSA and HEI Region(1 pg, 2 MB, 11/17/2000)
• Attachment L (Part 1): Annual Distributions of Day of Week Average PM2.5 Concentrations by MSA and HEI Region(1 pg, 2 MB, 11/17/2000)
• Attachment L (Part 2): Quarterly Distributions of Day of Week Average PM2.5 Concentrations by MSA and HEI Region(1 pg, 6 MB, 11/17/2000)
• Attachment M: Annual and Quarterly Distributions of 24-Hour Average PM2.5 Concentrations by Monitor (Grouped by MSA)(1 pg, 3 MB, 11/17/2000)
• Attachment N: Annual and Quarterly Distributions of Hourly Average PM2.5 Concentrations at Continuous Monitors(1 pg, 1 MB, 11/17/2000)
• Attachment O: Annual, Quarterly, and Day of Week Hourly Average PM2.5 Concentrations at Continuous Monitors(1 pg, 756 K, 11/17/2000)
• Attachment P: Annual Profile of Hourly Average and 24-Hour Moving Average PM2.5 Concentrations at Continuous Monitors(1 pg, 631 K, 11/17/2000)