AS 1807.22:2000 pdf – Cleanrooms, workstations, safety cabinets andpharmaceutical isolators-Methods of test Method 22: Determination of air barrier containment of laminar flow safety cabinets.
(b) Set the aerosol photometer to the identical sensitivity level previously used to determine the filter and filter installation integrity (see AS 1807.6).
NOTE: This should not be commenced until the background aerosol concentrations in the room have reached a steady state.
(c) Set the air pressure on the aerosol generator at 140 ±5 kPa with a single Laskin nozzle operating, release aerosol at a distance of 25 ±1 mm from, and at right angles to the inside plane of the viewing window at a series of test positions with the centre of the hose outlet 25 ±1 mm below the viewing window. The test positions shall be approximately 50 mm (centre of hose) from both inner side walls of the cabinet and at intervals of approximately 100 mm between these points (see Figure I).
(d) Operate the aerosol photometer at each test position for at least 10 s. Where an intermittent penetration reading greater than 0.01% above the ambient concentration is obtained, continue for at least a further 30 s.
(e) Using the anemometer, measure the air velocity of the exhaust air on the face of the perforated. removable guard at its centre point and record the value.
(f) If adjustments are made to the exhaust filter air flow rate, laminar flow conditions for the cabinet should be re-checked in accordance with AS 1807. I.
(g) Measure pressure drops across all HEPA tlters after barrier containment test and record the values.
8 REPORT The following information shall be reported:
(a) The test liquid used. If the test liquid is not DOP. the report shall state that the results may not be identical to those which would be obtained using DOP.
(b) For each test position, whether aerosol penetrations exceeded 0.01% more than an average of once per 10 s during the total test period.
(c) The initial pressure drops across all HFPA filters.
(d) The pressure drops across all HEPA filters after the barrier containment test.
(e) The air velocity of the exhaust air on the face of the perforated removable guard.
(f) Any interference, such as local grilles, diffusers, personnel traffic, which may have affected the result.
(g) If adjustments or repairs have been made during testing. the final test report shall note this action and shall report the relevant information, as above, before and after all adjustments or repairs made.
(h) Reference to this Australian Standard, i.e. AS 1807.22.
AS 1807.22:2000 pdf – Cleanrooms, workstations, safety cabinets andpharmaceutical isolators-Methods of test Method 22: Determination of air barrier containment of laminar flow safety cabinets
