Labconco 3970202 User Manual - page 36

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Chapter 6: Maintaining Your Filtered PCR Enclosure

4.  Using the “^” or “ν” keypads, respectively, increase or 

decrease the numerical value until it equals 30 (2'), 20 (3'). 15 

(4') for the Purifier Filtered PCR enclosure at 55 fpm 

downflow velocity. 

5.  Press the “ENTER” Keypad. The photometer will scan for 15 

seconds, and then the “0” keypad will flash. Press the “Enter” 

keypad. The unit will scan for 5 seconds, the display will read 

“0000,” and the unit will sound a confirming tone. 

6.  Set the valve to “DOWNSTREAM.” Place the palm of your 

hand over the sampling port of the pistol. There should be a 

strong vacuum at this port. If the vacuum is weak, contact Air 

Techniques Hamilton Associates. 

7.  Turn the enclosure on and let it operate for a minimum of 5 

minutes.   

8.  If necessary, adjust the speed control of the enclosure to 

maintain the following downflow airflows at 55 fpm; 2' 

(230cfm), 3' (340 cfm), 4' (460 cfm.) 

9.  Position the aerosol generator discharge in the intake of the 

prefilter on top of the enclosure.  

10. Start the aerosol generator (Pressure to be 10 +/- 1 PSIG). 

Ensure that one Laskin nozzle is in the “open” position.  

11. Allow the generator to operate for a minimum of 15 seconds. 

Scan the downstream exhaust side of the HEPA filter by 

passing the sampling nozzle of the gun in slightly overlapping 

strokes over the entire surface the filter, with the sampling port 

not more than 1 inch from the surface of the filter media. Scan 

the entire periphery of the filter and the gasket between the 

filter frame and the enclosure frame. Scanning shall be done at 

a traverse rate of not more than 2 inches per second. 

Acceptance 

Aerosol penetration shall not exceed 0.01 percent measured by the 

photometer.