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AQS Guidelines for Reporting 5-minute SO2 Data January 3, 2011

Dear AQS User:

Please use these guidelines when reporting the 5-minute SO2 data. (These are specifically for the SO2 reporting changes that were outlined in the November 3, 2010 memo “AQS Technical Note – NAAQS Reporting Issues for NO2 and SO2 NCORE Reporting Issues for NOy and trace-level gases.”)

If you are reporting: Use AQS Use AQS Use POC:

Notes

maximum 5-minute SO2 average from each hour

42406

1

Use of POC 1 is suggested but not required.

Meets the reporting requirement for SO2 5-minute data. (Other option is to load all the 5-minute data. See below.)

all of the twelve 5minute averages from each hour

42401

H

Often 42401 duration “1” data is reported as POC 1, so the use of POC 2

(if available) is suggested but not required.

Meets the reporting requirement for SO2 5-minute data.

(Other option is to load the maximum 5minute average for each hour. See

parameter code: duration code: above.)

Since “42401” is also used for hourly SO2 (duration 1) data, a new POC must be established. If you try to load 5minute data to the existing monitor being used for hourly data, you will get the error: “Sample duration cannot change within a calendar year.”

If using this option, the maximum 5 minute average for each hour does not have to be identified and separately reported. Before loading any 5-minute SO2 raw data into AQS, establish the new monitor with the appropriate parameter and POC.