For a wet scrubber subject to operating limits for pressure drop and scrubber water flow rate in §63.9890(b), you must establish site-specific operating limits according to the procedures in paragraphs (a) and (b) of this section.

(a) Using the continuous parameter monitoring system (CPMS) required in §63.9920, measure and record the pressure drop and scrubber water flow rate at least every 15 minutes during each run of the particulate matter performance test.

(b) Compute and record the average pressure drop and scrubber water flow rate for each individual test run. Your operating limits are the lowest average individual pressure drop and scrubber water flow rate values in any of the three runs that meet the applicable emission limit.