Filter replacement criteria for supply air ceiling filters (4 determination methods, priority: pressure difference > leak detection > appearance > usage duration)
\n1. Core determination: Pressure difference value (the most standard, GMP \/ hospital mandatory basis)
\nEach filter is equipped with an independent pressure difference meter. If the pressure difference exceeds the limit, it should be replaced immediately, regardless of the usage time.
\nPrimary efficiency filter (G3\/G4)
\nInitial pressure difference: 40-60 Pa
\nFinal resistance threshold: \u2265 100 Pa
\nTreatment: Can be disassembled for water washing. If the pressure difference remains high after washing, it should be replaced.
\nIntermediate efficiency filter (F7\/F8\/F9)
\nInitial pressure difference: 70-110 Pa
\nFinal resistance threshold: \u2265 200 Pa
\nTreatment: Cannot be washed. If the pressure difference meets the standard, it should be replaced immediately.
\nHEPA\/ULPA high-efficiency filter (H13\/H14)
\nJudgment rule: Actual pressure difference \u2265 initial pressure difference \u00d7 2
\nExample: Newly installed high-efficiency filter with an initial pressure of 120 Pa, rising to 240 Pa, must be replaced.
\nSupplement: The fan automatically increases frequency, the air volume significantly decreases, and the room fails to reach the set cleanliness level, which are basically caused by filter blockage and increased pressure difference.
\n2. Leak detection determination (specific to high-efficiency filters, replace immediately if leakage occurs)
\nOnly for the end HEPA\/ULPA filters, no leak detection is required for the primary and intermediate efficiency filters.
\nAnnual third-party PAO\/DOP aerosol leak detection;
\nSingle measurement point leakage efficiency not up to standard, frame sealing leakage;
\nFilter body has penetrating leakage points.
\nAny one of the above conditions is met, regardless of the pressure difference, it must be replaced immediately, otherwise the cleanliness level will not meet the requirements and the acceptance cannot be passed.
\n3. Visual inspection of appearance (quick judgment during daily inspection)
\nPrimary \/ intermediate efficiency visible features
\nLarge areas of blackening on the filter surface, thick accumulated dust, water washing cannot restore transparency;
\nFilter material damage, frame deformation, sponge sealing strip detachment;
\nMoisture, mold, water stains, oil stains adhering.
\nHigh-efficiency filter appearance abnormal (replace immediately)
\nFilter paper collapse, wrinkles, damage, holes;
\nWater accumulation inside the box, filter material moldy and yellowish;
\nSealing glue cracking, filter edge and corner deformation and leakage;
\nLong-term fumigation disinfection causing filter material brittleness and powder shedding.
\n4. Supporting judgment based on environment and operating conditions
\nThe following phenomena indicate that the filter has failed or is severely clogged:
\nThe particle concentration in the clean area continuously exceeds the standard, and the settled bacteria and airborne bacteria are not up to standard.
\nThe air velocity at the supply air ceiling outlet is uneven\uff0c with no wind in some areas\uff1b
\nUnder the same fan frequency\uff0c the indoor pressure difference continuously decreases\uff0c unable to maintain positive pressure\uff1b
\nFan noise increases\uff0c severe heating\uff0c long-term full-load operation.
\n5. Time is only an auxiliary reference (cannot be the sole basis for replacement)
\nOnly when pressure difference\uff0c leak detection\uff0c and appearance are all normal\uff0c it serves as a management warning\uff1a
\nPrimary efficiency\uff1a The longest 3 months without cleaning is recommended for maintenance\uff1b
\nIntermediate efficiency\uff1a After 12 months\uff0c it is recommended to check the pressure difference\uff1b
\nH14 high-efficiency after 1.5 years\uff0c H13 after 2 years\uff0c ULPA after 5 years\uff0c conduct comprehensive leak detection and pressure difference measurement.
\n6. Summary of replacement priority (operational sequence)
\nPressure difference exceeds limit \u2192 Replace immediately (the first standard)
\nPAO leak detection exceeds standard \u2192 Replace immediately
\nFilter material damage\uff0c mold\uff0c deformation \u2192 Replace immediately
\nLong-term non-compliance with cleanliness level\uff0c insufficient air volume \u2192 Investigate the filter and replace
\nReaches the preset usage period \u2192 Check the pressure difference\uff0c replace as needed<\/p>","protected":false},"excerpt":{"rendered":"
Filter replacement criteria for supply air ceiling filters (4 determination methods, priority: pressure difference > leak detection > appearance > usage duration) 1. Core determination: Pressure difference value (the most standard, GMP \/ hospital mandatory basis) Each filter is equipped with an independent pressure difference meter. If the pressure difference exceeds the limit, it should […]<\/p>","protected":false},"author":12,"featured_media":5484,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[92],"tags":[],"class_list":["post-5629","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-industry-technology"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/posts\/5629","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/users\/12"}],"replies":[{"embeddable":true,"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/comments?post=5629"}],"version-history":[{"count":1,"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/posts\/5629\/revisions"}],"predecessor-version":[{"id":5630,"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/posts\/5629\/revisions\/5630"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/media\/5484"}],"wp:attachment":[{"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/media?parent=5629"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/categories?post=5629"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/tags?post=5629"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}