Document ID: EPA-HQ-OAR-2017-0015-0107
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2023-01-05T05:00Z

Summary of Data Quality Issues with Lhoist Organic HAP Test reports
Method 18:
Apex  -  The bag sampling and analytical approach used at Apex is inappropriate for several of the compounds due to the potential for loss on the wall of the bag. A hold time study was not performed on the bag (per Method 18) and TO-15 analysis was performed by the laboratory, which does not require a recovery study which could have mitigated some of the sampling issues.
Nelson  -  There were issues with the spiking of the traps making an assessment of validity difficult (the issues were noted int eh laboratory report). 
All reports  -  All of the reports described the bag method, though Alabama and Nelson performed the sorbent trap methodology (not a significant issue, just raised for clarity).

Method 320:
All reports  -  No record of a validation study at these or similar sources. 
Apex and Nelson - There were issues with the dynamic spiking, the difference between the tagged cylinder value and the named value for formaldehyde were larger than would be expected. Only 1 of the 3 required dynamic spikes were done. The appearance of the data suggests that some selectivity of the data to meet the requirements, this was more prevalent in the HCl spikes, but raises questions.
Nelson  -  There was no spiking of the organic compounds, but only HCl.
Alabama  -  A spike level higher than is appropriate was chosen for acetaldehyde. The data indicated values below zero for most of the test, sometime well below zero. This indicates possible issues with he algorithm used in the spectroscopy. Data should have been reported as less than the detection limit and not zero.