Appendix A CEMS Inspection Sheet
4. Dilution Air Systems (Including Air Cleaning Subsystem)
What to Check
Has the dilution probe orifice been changed? If the orifice has been changed, ask if there is a procedure for changing the orifice in the QA/QC Plan, what prompts a change, and how the dilution ratio is verified.
Is the dilution probe ejector pump vacuum at or below the certification value? How often is it checked?
What is the dilution ratio? Check the dilution air and analyzer flow settings. How are these set and verified? These should all be described in the QA/QC plan.
Are correction factors applied to the dilution ratio for changes in pressure, temperature, or molecular weight? Have these been changed since the last RATA? Changes to correction factors should be recorded in the maintenance log,. QA testing may also be required . (Also see Table 8 - DAHS).
Check the inlet and outlet pressures of CO2 air cleaner filter. Compare levels to the QA/QC Plan.
How often are the air cleaning filters and drying agents replaced? Compare to the QA/QC plan.
5. Source Level Extractive Systems
What to Check
Check the umbilical lines entering the CEMS shelter for condensation (visible water drops).
For a dry system using chillers check the chiller temperature. What is the proper temperature range, and how often is it verified? Compare against the QA/QC Plan.
Part 75 Field Audit Manual – July 16, 2003 Page A-4