{"id":5544,"date":"2026-06-24T14:02:23","date_gmt":"2026-06-24T06:02:23","guid":{"rendered":"https:\/\/www.bacintl.com\/?p=5544"},"modified":"2026-06-24T08:43:39","modified_gmt":"2026-06-24T00:43:39","slug":"the-differences-between-negative-pressure-laminar-flow-workbench-and-vertical-flow-workbench","status":"publish","type":"post","link":"https:\/\/www.bacintl.com\/fr\/the-differences-between-negative-pressure-laminar-flow-workbench-and-vertical-flow-workbench\/","title":{"rendered":"The differences between negative pressure laminar flow workbench and vertical flow workbench"},"content":{"rendered":"

Negative pressure laminar flow workbench vs. Ordinary vertical flow clean bench – Core differences
\nFirst, let’s clarify the essence of these two devices:
\nVertical flow workbench (clean bench): Internal positive pressure, only protecting the samples
\nNegative pressure laminar flow workbench (weighing chamber \/ II-level biosafety cabinet): Internal negative pressure, protecting the person + environment + samples<\/p>\n

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\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Vertical flow ultra-clean workstation\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 Negative pressure laminar flow workbench<\/p>\n

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\u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0 \u00a0Vertical flow structure diagram<\/p>\n

\nI. Core pressure and airflow principles (the most fundamental difference)
\n1. Ordinary vertical flow workbench (positive pressure)
\nThe air pressure inside the cabinet is higher than that of the external room (positive pressure)
\nAirflow path: Top HEPA flows downward in a vertical laminar flow \u2192 passes through the tabletop \u2192 is directly discharged from the bottom \/ front window into the room
\nAirflow logic: Clean air is pushed outwards to block the entry of dirty air from outside; however, pollutants within the cabinet will drift outwards along the airflow
\nThere is no active inward suction design, and the front window has no negative pressure supply
\n2. Negative pressure laminar flow workbench (negative pressure type weighing hood \/ biosafety cabinet)
\nThe air pressure inside the cabinet is lower than that of the external room (negative pressure)
\nThe airflow is divided into two paths:
\nTop vertical clean laminar flow protects the sample;
\nThe operation window continuously supplies air inward (negative pressure suction), forming an air curtain to seal the opening
\nAll contaminated air containing dust \/ aerosols passes through HEPA filtration before being discharged (some are directly discharged outside)
\nThe pressure difference meter monitors the negative pressure in real time, and alarms in case of pressure loss, preventing harmful substances from spilling out
\nII. The protective objects are completely different<\/p>\n\n\n\n\n\n
Equipment type<\/td>\nProtecting samples<\/td>\nProtecting operators<\/td>\nProtecting laboratory environment<\/td>\n<\/tr>\n
Vertical flow clean bench<\/td>\n\u2705 Strong<\/td>\n\u274c No protection<\/td>\n\u274c Pollutants discharged directly into the room<\/td>\n<\/tr>\n
Negative pressure laminar flow workbench<\/td>\n\u2705 Ensures cleanliness with laminar flow<\/td>\n\u2705 Prevents inhalation of dust \/ pathogenic bacteria<\/td>\n\u2705 Dual filtration of exhaust air without leakage<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Summary:
\nVertical flow: Only protects the samples, not the person. Toxic, allergenic, and pathogenic bacteria must not be used.
\nNegative pressure laminar flow: Triple protection, specifically for handling dust, powder, microorganisms, and toxic raw materials.
\nIII. Structural Configuration Differences
\nVertical flow workbench
\nOnly one supply fan + top HEPA;
\nNo independent exhaust system, no external connection pipes;
\nNo negative pressure monitoring, no pressure difference alarm;
\nSimple tabletop, no sinking dust collection duct.
\nNegative pressure laminar flow workbench (weighing room \/ negative pressure cabinet)
\nDual fan system: Supply fan (vertical laminar flow) + negative pressure exhaust fan;
\nDouble-layer high-efficiency filtration: Supply HEPA + Exhaust HEPA, some equipped with activated carbon;
\nStandardized pressure difference meter, negative pressure sound and light alarm;
\nBottom sinking dust collection tank, dust accumulation prevention;
\nMostly reserved pipe interfaces, can be directly discharged outdoors;
\nThe cabinet has higher sealing requirements to prevent air leakage.
\nIV. Applicable Scenarios (Selection Key)
\nVertical flow workbench (positive pressure) applicable
\nCell culture, tissue culture inoculation, ordinary sterile reagent preparation;
\nElectronic chips, optical components, non-dust and non-toxic components assembly;
\nNon-toxic, non-dust, non-pathogenic ordinary sterile operations;
\nHospital dispensing, ordinary sterile testing.
\nProhibited: Drug powder weighing, highly toxic raw materials, pathogenic bacteria, allergenic powder, volatile toxic reagents.
\nNegative pressure laminar flow workbench applicable
\nPharmaceutical GMP powder weighing, sampling, filling (highly active drugs, hormones, anti-tumor drugs);
\nPathogenic bacteria, viruses, pathogenic bacteria operation (II-level biosafety cabinet);
\nChemical, fragrance, heavy metals, allergenic dust operation;
\nProcesses generating a large amount of dust and aerosols, requiring prevention of operators from inhaling.
\nV. Usage Risk Comparison
\nVertical flow workbench risk
\nWhen handling powders \/ bacteria, aerosols will overflow from the front window along the vertical airflow and be directly inhaled by the operator, causing occupational exposure, cross-contamination, and contamination of the entire laboratory.
\nNegative pressure laminar flow workbench safety logic
\nThe opening continuously sucks inward, dust and aerosols will not spread outward; even if there is dust on the tabletop, it will be sucked in by the negative pressure and filtered by the exhaust, completely preventing leakage.
\nVI. Simple Sentence to Distinguish
\nVertical flow clean bench (positive pressure): Clean air blows downward, outwards, only protecting the products, suitable for clean and non-toxic samples;
\nNegative pressure laminar flow workbench: Top clean air protects the samples, the window sucks inward to lock the dust, protecting both the person, the environment, and the samples, suitable for toxic, dusty, and high-risk pathogenic operations.<\/p>","protected":false},"excerpt":{"rendered":"

Negative pressure laminar flow workbench vs. Ordinary vertical flow clean bench – Core differences First, let’s clarify the essence of these two devices: Vertical flow workbench (clean bench): Internal positive pressure, only protecting the samples Negative pressure laminar flow workbench (weighing chamber \/ II-level biosafety cabinet): Internal negative pressure, protecting the person + environment + […]<\/p>","protected":false},"author":12,"featured_media":5547,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[23],"tags":[],"class_list":["post-5544","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/posts\/5544","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=5544"}],"version-history":[{"count":2,"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/posts\/5544\/revisions"}],"predecessor-version":[{"id":5550,"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/posts\/5544\/revisions\/5550"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/media\/5547"}],"wp:attachment":[{"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/media?parent=5544"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/categories?post=5544"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/tags?post=5544"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}