Theoretical Upstream Concentration; Upstream Concentration Sampling - Labconco Logic+ A2 Technical Manual

4. If the model has a pre-filter installed on the towel catch, remove it for testing.
5. If the aerosol generator requires pressurized air, connect the air line. Turn on the
appropriate number of Laskin nozzles for the model under test based on Table
10-1 to ensure they are each working properly.
6. Verify the generator's air pressure is 23 psi.
7. Turn on the photometer and allow it to operate for a minimum of 5 minutes.
Leave the valve in the "CLEAR" setting.

Theoretical Upstream Concentration

If the biosafety cabinet has been used with biohazards, toxic chemicals, or
radioisotopes, the Upstream Sample Tube cannot be used (Figure 10-1). Testing at
Labconco has shown the actual concentration varies from the theoretical value. Table
10-1 shows the actual vs. calculated concentrations for Type A2 models. Establish the
100% and 0% concentration levels for the photometer using the actual values provided
in Table 10-1 for the model being tested.

Upstream Concentration Sampling

If the biosafety cabinet has NOT been used with biohazards, toxic chemicals, or
radioisotopes, the Upstream Sample Tube can be used (Figure 10-1).
You never know what a biosafety cabinet has been exposed to, so it is always
recommended to surface decontaminate any components prior to working inside the
biosafety cabinet and/or removing components from the biosafety cabinet.
1. Locate the Upstream Sample Tube on the right side, protruding from the rear
baffle. See Figure 10-1. On some models this tube is clear.
2. Pull the Upstream Sample Tube forward. Do not remove the cap yet.
3. When prompted by the photometer, turn on the appropriate number of Laskin
nozzles on the aerosol generator, uncap the Upstream Sampling Tube and
sample the upstream concentration to establish the 100% concentration level.
4. Establish the 0% concentration level according to your photometer's instructions.
Figure 10-1
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Figure 10-2