OAR Policy and Guidance Metarecord

Document Title/Subject: Use of Collocated PM2.5 Data and Parameter Occurrence Codes Related Documents:	Signed by: David Misenheimer Signature Date: 12/21/99 Contact: Michael Papp	Filename(s): URL(s): 25colo.pdf
Regulatory Authority: Title 1	Division/Director: Emissions, Monitoring, and Analysis Division (OAQPS) / David Mobley	Submitted By: papp.michael	OGC Contact: Kevin McLean OGC Phone#: 202-564-5564	Internet Contact: Jeff Clark
Document Type: Policy & Guidance Memos	EPA Document Number: Federal Register:	Supersedes:
Subject Category: AIR	Keywords: Particulate matter Air Quality Monitoring PM2.5 Collocated Data	Terms: Air quality
Abstract: The new guidance is intended to clarify any potential ambiguities in the QA Handbook Method 2.12 and to conform with a July 24, 1989 memorandum on the handling of PM10 collocated data. Accordingly, the memo reiterates that data from a collocated sampler can be substituted for the primary sampler if the primary sampler was not operating or did not produce a valid measurement for that same day. The memo also suggests that State and local agencies enter the substituted collocated data as parameter occurrence codes 2 (POC-2).