An air monitoring program can run sound equipment all year and still come out of an audit with findings, because an audit measures what a program can show, not just what it does. EPA's technical systems audits review data, recordkeeping, and documentation alongside the monitoring stations themselves, and compare what they find against regulations, EPA guidance, and the program's own quality system documents.[2] The programs that get through cleanly are usually the ones whose paperwork tells the same story as their field operations.
Records Come First
Under 40 CFR Part 58, Appendix A, each primary quality assurance organization must receive a technical systems audit at least every three years.[1] Much of the work starts before anyone arrives on site. Auditors send a pre-audit questionnaire and review the program's data and documentation in advance, and the on-site visit then covers interviews, station inspections, and a review of records and support facilities.[2][3] A program that can hand over an organized, current file makes that process straightforward. One that has to reconstruct its records on the spot makes every other part of the audit harder.
Calibration: The Core Paper Trail
The USEPA requires annual recertification of the calibration devices used to calibrate air monitoring instrumentation.[5] At the sampler level, Tisch Environmental recommends a full calibration check quarterly or after any major component replacement.[6] Each of those events needs a record: the transfer standard used, its certification date, the readings taken, and who performed the work. A calibration that happened on schedule but can't be shown on paper is difficult to defend in a review.
Maintenance, Data, and Chain of Custody
Preventive maintenance needs a date and a name attached to it, not a memory of it happening. Monitoring data needs to be complete, or any missing periods need a documented explanation. If filters or samples move between the field and a lab, each handoff needs a name and a date, so the sample's history can be traced if a result is ever questioned. These records are what allow a program to show, after the fact, that its data was collected the way its procedures say it was.
A Few Things Worth Knowing
Training shows up in real audit findings
Quality system documents need to be current
QA/QC needs a recorded result, not just a passing grade
How a Technical Systems Audit Unfolds
| Phase | What Happens | What It Draws On |
|---|---|---|
| Preparation | Pre-audit questionnaire and advance data review[2][4] | Data from EPA's Air Quality System and the program's questionnaire responses |
| On-site visit | Staff interviews, station inspections, and records review[2] | Recordkeeping, documentation, and support facilities |
| Report | A written summary of findings[4] | Comparison to regulations, EPA guidance, and the program's quality system documents[2] |
| Follow-up | Corrective action process to address findings[4] | The program's response and corrective action plan |
Why This Matters Beyond the Audit
An audit is a checkpoint on top of something that should already be happening. Programs that move through it smoothly tend to be the ones where documentation was built alongside the monitoring from the start, not added afterward. California's PQAO training even encourages monitoring organizations to conduct their own internal TSA rather than waiting for CARB or EPA to arrive.[4]
Key Takeaways
- EPA technical systems audits are required at least every three years and review records alongside field operations
- Calibration devices require annual recertification, and each calibration needs a complete record
- Maintenance logs and data records need dates, names, and documented explanations for any gaps
- Chain of custody needs a name and date at every handoff
- Training requirements and current QAPPs and SOPs appear in real audit findings
- Running an internal self-audit before the official one is an encouraged practice
None of this is complicated once it's built into the routine. It just has to be built before the auditor shows up, not while they're standing in the room.
If calibration paperwork is the piece most likely to slip in your program, Tisch Environmental's NIST-traceable calibration lab can help keep your calibrators and their certificates current. Schedule Calibrator Recertification