An official website of the United States government.

We've made some changes to If the information you are looking for is not here, you may be able to find it on the EPA Web Archive or the January 19, 2017 Web Snapshot.

AQS Release Notes for June - July 2018

  1. The AQS RSS Feed is operational again.  It is accessible at the following URL: Please subscribe to the AQS News feed there.  All future release notes for AQS patches and outages will be posted there instead of being distributed via a mass email.
  2. There will be a production outage on Sunday evening, August 5, 2017, from 8:00 PM Eastern time to 7:00 AM on Monday, August 6, 2018.  The outages is for server operating system upgrades.
  3. An update to the AQS User’s Guide was posted to the AQS website on July 18.  It can be accessed at the following link:  AQS User Guide (PDF)
  4. The valid ranges for Assessment Concentration for 1-Point QC transactions have been updated to reflect the 2016 changes to 40 CFR Part 58 Appendix A Section 3.1.1.  For the year 2018 and following, if a 1-Point QC transaction is submitted with the assessment concentration not in the valid range, it will be accepted with a warning, but it will not count towards completeness in the Data Quality Indicator Report (AMP256) and the Certification Evaluation Report (AMP600).  A new column, “Validity”, has been added to the Raw QA Assessment Report (AMP251) to show if the concentration is in the required range (‘Y’) or not (‘N’).  The valid ranges are:
    1. CO:                       0.5 – 5.0 PPM
    2. Ozone:                 0.005 – 0.080 PPM
    3. SO2:                      5.0 – 80.0 PPB
    4. NO2:                     5.0 – 80.0 PPB
  5. For the 2015 Ozone standard, it was noted that the Monitor-Level Quarterly Percent Complete values computed by AQS were not Correct.  (Note:  This was for monitor summaries, not site summaries.)  We investigated and found that the monitor summaries for the 2015 standard had not been changed to reflect a maximum of 17 8-hour summaries per day.  AQS was modified to not create monitor-level 8-hour summaries for hours 0 (midnight) to 6 AM, and the daily, quarterly, and annual completeness calculations were changed to use 17 as the maximum number per day, for the 2015 Ozone standard.  All existing summary records were corrected.
  6. The Maintain Monitor form was updated to show the counts of any Raw Data, Blanks Data, or QA data outside of Sample Periods.
  7. Fixed problem with the Design Value report where users were not getting credit toward completeness for ‘BG’ null codes (“Missing Day Assumed less than standard”) that were regionally concurred.
  8. Changed the validity criteria for CO 1-hour Annual Summaries, to show the annual summary as valid whenever there is any data for year.
  9. Fixed problem with Design Value report validity indicator for NO2, when there was incomplete data that should have been marked as valid because of the substitution test described in Part 50 Appendix S.