Here is a set of standard operating procedures for the **High Efficiency Filter Integrity Testing (PAO Leak Detection Method)** commonly used in cleanrooms, specifically for automatic double-door and shower rooms. It is simple, practical, and concise.
\nHigh Efficiency Filter Integrity Testing (PAO Aerosol Leak Detection) Procedure
\nI. Preparation
\nTools
\nAerosol Generator (PAO\/DOP)
\nAerosol Photometer (particle counter can also be used as a substitute)
\nClean cloth, alcohol, marker pen, record sheet
\nPersonnel
\nWear clean suits, gloves, and masks
\nEquipment Status
\nThe door of the shower room is closed, and the room is kept sealed.
\nClean the outlet surface and nozzles of the high-efficiency filter in advance.
\nII. Dust Generation (Establishing Upstream Concentration)
\nPlace the PAO aerosol generator at the inlet end of the shower room (outside the primary filter or in the return air box).
\nTurn on the generator and let the PAO oil mist enter the duct along the airflow and pass through the high-efficiency filter evenly.
\nTake samples in the upstream duct of the high-efficiency filter using the photometer,
\nAdjust the dust generation rate to make the upstream concentration reach 10% to 20% of the photometer’s measurement range and stabilize.
\nPurpose: To ensure that the downstream can accurately detect the leakage.
\nIII. Downstream Leak Detection (Core Step)
\nPlace the photometer probe on the outlet surface of the high-efficiency filter, 2 to 5 cm away from the filter surface.
\nScan in the following order at a uniform speed:
\nThe entire filter material surface
\nSealing areas between the filter material and the frame
\nSealing areas between the frame and the box installation slot
\nThe four corners of the high-efficiency filter
\nThe scanning speed should not exceed 5 cm\/s.
\nObserve the photometer reading:
\nIf there is no significant increase in the reading \u2192 No leakage
\nIf the reading suddenly increases and exceeds the upper limit \u2192 There is a leakage point
\nIV. Leakage Judgment Criteria
\nIf any of the following conditions is met, it is considered unqualified and needs to be replaced or repaired:
\nThe photometer reading exceeds 0.01% of the upstream concentration
\nThere is a clear and continuous concentration peak
\nContinuous leakage signals occur at the frame and sealing strip areas
\nV. Repair and Re-test (If Repair is Allowed)
\nMark the location of the leakage point.
\nUse special silicone \/ sealant to repair the filter material or frame.
\nAfter the repair is completed\uff0c wait for curing\uff0c and then conduct a complete scan for leak detection again.
\nIf there is still leakage after repair \u2192 Replace the high-efficiency filter directly.
\nVI. Conclusion and Record
\nTurn off the PAO generator and continue to let the fan run for 10 to 15 minutes to expel residual aerosols.
\nFill in the test record\uff1a Testing date
\nUpstream concentration
\nLeakage situation
\nTreatment result (qualified \/ repair \/ replacement)
\nSimple alternative solution (without PAO equipment)
\nIf there is no PAO system, the particle counter method can be used:
\nNormal air blowing for the air shower
\nScan the outflow surface of the high-efficiency filter with a particle counter
\nIf the number of particles in a certain area suddenly increases, it indicates a leakage
\nCompared with the cleanroom standards, if the result exceeds the limit, it is judged as unqualified
\nImportant reminder
\nThe high-efficiency filter of the air shower in the cleanroom generally does not recommend repeated repairs; if there is a leakage, it is better to replace it directly.
\nThe detection must be carried out under the condition that the fan is running normally and the door is closed and sealed.
\nSpecial attention should be paid to the sealing of the door frame and the air leakage of the box for double-door air showers to avoid misjudgment.<\/p>","protected":false},"excerpt":{"rendered":"
Here is a set of standard operating procedures for the **High Efficiency Filter Integrity Testing (PAO Leak Detection Method)** commonly used in cleanrooms, specifically for automatic double-door and shower rooms. It is simple, practical, and concise. High Efficiency Filter Integrity Testing (PAO Aerosol Leak Detection) Procedure I. Preparation Tools Aerosol Generator (PAO\/DOP) Aerosol Photometer (particle […]<\/p>","protected":false},"author":3,"featured_media":4450,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[92],"tags":[],"class_list":["post-5235","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-industry-technology"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.bacintl.com\/ar\/wp-json\/wp\/v2\/posts\/5235","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.bacintl.com\/ar\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.bacintl.com\/ar\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.bacintl.com\/ar\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.bacintl.com\/ar\/wp-json\/wp\/v2\/comments?post=5235"}],"version-history":[{"count":1,"href":"https:\/\/www.bacintl.com\/ar\/wp-json\/wp\/v2\/posts\/5235\/revisions"}],"predecessor-version":[{"id":5236,"href":"https:\/\/www.bacintl.com\/ar\/wp-json\/wp\/v2\/posts\/5235\/revisions\/5236"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.bacintl.com\/ar\/wp-json\/wp\/v2\/media\/4450"}],"wp:attachment":[{"href":"https:\/\/www.bacintl.com\/ar\/wp-json\/wp\/v2\/media?parent=5235"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bacintl.com\/ar\/wp-json\/wp\/v2\/categories?post=5235"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bacintl.com\/ar\/wp-json\/wp\/v2\/tags?post=5235"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}