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Follow-up Information on CF4 Abatement DRE Testing 5-9-2012 

1. SIA to provide a list of CF4 DRE trials that operated outside of manufacturer’s 

recommendations to inform the proposal technical support. 

The table below lists the tests performed at one facility in 2011, of which 15 of the 20 tests did 

not meet the manufacturer’s expected DRE. The complete table of data was provided to EPA in 

the file “Etch DRE with flow data.xls”. 

Discussions with the abatement system manufacturer have indicated that where the inlet flow 

volume exceeds 250 lpm (8 or the 15 tests in the table below) or the outlet flow volume exceeds 

1100 lpm (4 of the 15 tests in the table below) the system was operating outside the 

manufacturer’s recommendations. Considering both parameters, this is the case for 10 of the 

15 systems. 

For the other 5 systems, other factors caused the low DREs. The SIA submittal to EPA 

“120329SIA EPA Abatement Answers final.doc” stated: “After a full assessment of the results of 

the abatement testing, it was determined that modifications were required in the maintenance 

procedures to validate that the fuel, O2, and combustion air flows and/or pressure settings were 

in accordance with the manufacturer’s recommended requirements. Maintenance checklists and 

the training for technicians servicing the units have been improved to more clearly define set-up 

requirements that apply at the completion of initial system installation and to the regular 

maintenance checks.” It is believed the other five units had low DREs because one or more of 

the referenced flow and pressure settings were operating outside of the manufacturer’s 

recommended ranges.

Abatement Unit CF4 DRE Measurements Below Manufacturer’s Expected DRE Value 

System 

ID Comments 

Abatement 

System Install 

Date 

Test Date 

(2012) 

Volume In 

(lpm) 

Volume Out 

(lpm) 

Dilution 

Factor 

Measured 

DRE (%) 

L 12-May-10 19-Sep 242.100 741.900 3.06 76.1 

D 6-Oct-04 2-Aug 97.100 882.200 9.08 68.0 

M Retest 3-Jul-07 8-Sep 178.000 1124.000 6.32 67.3 

A 14-Mar-07 13-Apr 272.010 944.280 3.47 49.0 

A Retest 14-Mar-07 15-Sep 182.900 658.500 3.60 47.3

O 13-Sep-04 7-Sep 218.400 853.800 3.91 42.5 

M 3-Jul-07 28-Apr 182.619 1156.575 6.33 39.7 

F Area Abatement Main and 

Backup Scrubber for F, E, and R 4-Nov-02 15-Sep 321.300 875.100 2.72 38.2 

E Area Abatement Main and 

Backup Scrubber for F, E, and R 4-Nov-02 15-Sep 306.700 845.100 2.76 31.0 

I Area Abatement Main and 

Backup Scrubber for I, J and S 18-Mar-03 18-Aug 339.200 802.800 2.37 28.7 
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J Area Abatement Main and 

Backup Scrubber for I, J and S 18-Mar-03 18-Aug 305.900 896.100 2.94 15.0 

Q 15-Jan-08 22-Sep 206.300 919.100 4.45 4.1 

B 28-Mar-07 21-Apr 375.018 1012.183 2.70 0.0 

G Area Abatement Main and 

Backup Scrubber for G, H and T 17-Jul-03 25-Aug 298.900 1171.600 3.92 0.0 

H Area Abatement Main and 

Backup Scrubber for G, H and T 17-Jul-03 25-Aug 298.600 1216.700 4.07 0.0 

Highlighted values indicate inlet and outlet flows to the abatement units that do not meet the 

manufacturer’s recommended flow levels and which had DREs below the manufacturer’s 

expected DRE value.