Filters That Cannot Be Accessed Or Scanned; Airflow Pattern Test - Thermo Scientific 1500 A2 Series Operating Manual

Filters that can be
Accessed and Scanned
(continued)
Filters that cannot be
Accessed or Scanned

Airflow Pattern Test

Thermo Scientific
4. If desired, and if the cabinet has not been used with hazardous
materials since an effective decontamination, the upstream
concentration can be measured. If desired, connect the photometer
sample hose to the appropriate (supply or exhaust) test hose connection
(exhaust test hose - right side / supply test hose - left side) from under
the work tray.
5. Using either the appropriate upstream challenge measurement or
calculated challenge value, set the photometer accordingly.
6. Scan the downstream side and perimeter of the filter as prescribed in
NSF/ANSI 49, Annex F.
Acceptance:
• Filters scanned – 0.01% of upstream concentration at any point.
Method:
1. Set up as in Steps 1 through 5 above
2. In the duct, downstream of the filter, sample in accordance with
NSF/ANSI 49.
Acceptance:
• Filters not scanned – 0.005% of upstream concentration
Description:
• Determines the internal and external behavior of the air movement.
Equipment:
• Cold smoke (titanium tetrachloride)
Method:
• Downflow:
Pass smoke across the centerline of the work surface, 4 inches (10 cm)
above the work opening.
• View Screen Retention:
Pass smoke 1 inch (2.5 cm) behind the window opening, 6 inches
(15 cm) above the work opening.
Section 8
Certification Testing
1500 Series A2 8-9