{"id":4717,"date":"2026-09-23T23:15:51","date_gmt":"2026-09-24T06:15:51","guid":{"rendered":"https:\/\/www.26yc.com\/air-filter-basics-how-air-filters-work\/"},"modified":"2026-10-08T23:36:08","modified_gmt":"2026-10-09T06:36:08","slug":"air-filter-basics-how-air-filters-work","status":"publish","type":"post","link":"https:\/\/www.26yc.com\/fr\/air-filter-basics-how-air-filters-work\/","title":{"rendered":"Bases des filtres d'air : comment fonctionnent et pourquoi les syst\u00e8mes CVC en ont besoin"},"content":{"rendered":"<h2>What an Air Filter Actually Does<\/h2>\n<p>An air filter is a barrier placed in an airstream to remove solid particles-dust, pollen, soot, fibres, bacteria and many viruses-before that air reaches people, equipment or a downstream process. In an HVAC system the same air may be recirculated dozens of times a day, so a filter is the component that keeps that loop clean.<\/p>\n<h2>How Filtration Works<\/h2>\n<p>No single mechanism captures every particle. Real filters combine four:<\/p>\n<ul>\n<li><strong>Interception<\/strong> &#8211; a particle following the airstream touches and sticks to a fibre.<\/li>\n<li><strong>Impaction<\/strong> &#8211; heavier particles cannot bend around fibres and embed themselves.<\/li>\n<li><strong>Diffusion<\/strong> &#8211; the random Brownian motion of sub-micron particles throws them onto fibres (dominant in HEPA media).<\/li>\n<li><strong>Electrostatic attraction<\/strong> &#8211; charged synthetic fibres pull in oppositely charged particles, boosting capture at low resistance.<\/li>\n<\/ul>\n<h2>Three Numbers That Define a Filter<\/h2>\n<table border=\"1\" cellpadding=\"6\" cellspacing=\"0\">\n<thead>\n<tr>\n<th>Term<\/th>\n<th>What it means<\/th>\n<th>Why it matters<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Efficacit\u00e9<\/td>\n<td>Share of particles removed, by size<\/td>\n<td>Higher = cleaner air, but usually higher resistance<\/td>\n<\/tr>\n<tr>\n<td>Pressure drop (\u0394P)<\/td>\n<td>Fan energy needed to push air through<\/td>\n<td>Lower = lower running cost; rises as the media loads<\/td>\n<\/tr>\n<tr>\n<td>Dust-holding capacity<\/td>\n<td>Mass of particles before end-of-life<\/td>\n<td>Higher = longer service life, fewer changeouts<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2>Why Every System Needs One<\/h2>\n<ul>\n<li>Protects occupants&#8217; health (allergy, asthma, infection control).<\/li>\n<li>Protects equipment-coils, fans and sensors last longer when clean.<\/li>\n<li>Keeps processes on-spec in pharma, food, electronics and labs.<\/li>\n<li>Reduces cleaning and repaint cycles in industrial buildings.<\/li>\n<\/ul>\n<p>Choosing the right stage-pre, medium or HEPA-is covered in our efficiency-class and application guides.<\/p>\n<div class=\"yc-related\">\n<h3>Articles connexes<\/h3>\n<ul>\n<li><a href=\"https:\/\/www.26yc.com\/fr\/primary-filters-g1-g4-panel-pocket-specifications\/\">Filtres primaires (pr\u00e9-filtres) G1-G4 : types \u00e0 panneau et pochette, sp\u00e9cifications, s\u00e9lection<\/a><\/li>\n<li><a href=\"https:\/\/www.26yc.com\/fr\/medium-efficiency-filters-f5-f9-specifications\/\">Filtres \u00e0 moyenne efficacit\u00e9 F5-F9 : types \u00e0 pochette, panneau et V-Cell, sp\u00e9cifications, s\u00e9lection<\/a><\/li>\n<li><a href=\"https:\/\/www.26yc.com\/fr\/hepa-ulpa-filters-h10-h14-specifications\/\">Filtres HEPA et ULPA H10-H14 : types mini-plis, \u00e0 s\u00e9parateur et bo\u00eetier, sp\u00e9cifications, s\u00e9lection<\/a><\/li>\n<li><a href=\"https:\/\/www.26yc.com\/fr\/which-air-filter-where-application-guide\/\" title=\"Quel filtre d&#039;air va o\u00f9 : guide d&#039;application par industrie et espace\">Quel filtre d'air va o\u00f9 : guide d'application par industrie et espace<\/a><\/li>\n<li><a href=\"https:\/\/www.26yc.com\/fr\/hws-oil-mist-filter-salt-mist-eliminator\/\" title=\"HWS Oil Mist Filter &amp;amp; Salt Mist Eliminator\">HWS Oil Mist Filter &amp;amp; Salt Mist Eliminator<\/a><\/li>\n<\/ul>\n<\/div>\n<h2>Questions fr\u00e9quemment pos\u00e9es<\/h2>\n<p><strong>How does an air filter actually capture particles?<\/strong><br \/>Media captures dust through impaction, interception, diffusion and electrostatic attraction as air passes through the fibres.<\/p>\n<p><strong>Why do HVAC systems need air filters?<\/strong><br \/>Filters protect coils and fans from fouling, maintain indoor air quality and help meet hygiene and health requirements.<\/p>\n<p><strong>What is dust-holding capacity?<\/strong><br \/>It is the total mass of particles a filter can hold before it reaches its final pressure drop and must be replaced.<\/p>\n<p><strong>Do filters clean both return and outdoor air?<\/strong><br \/>In mixed-air systems both streams are filtered, and correct placement of pre and final stages determines how well each is protected.<\/p>","protected":false},"excerpt":{"rendered":"<p>Air filters trap dust, pollen and microbes from moving air. Learn how filtration works, the key terms-efficiency, pressure drop, dust-holding-and why every HVAC system needs one.<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[109],"tags":[],"class_list":["post-4717","post","type-post","status-publish","format-standard","hentry","category-filter"],"_links":{"self":[{"href":"https:\/\/www.26yc.com\/fr\/wp-json\/wp\/v2\/posts\/4717","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.26yc.com\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.26yc.com\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.26yc.com\/fr\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.26yc.com\/fr\/wp-json\/wp\/v2\/comments?post=4717"}],"version-history":[{"count":4,"href":"https:\/\/www.26yc.com\/fr\/wp-json\/wp\/v2\/posts\/4717\/revisions"}],"predecessor-version":[{"id":5076,"href":"https:\/\/www.26yc.com\/fr\/wp-json\/wp\/v2\/posts\/4717\/revisions\/5076"}],"wp:attachment":[{"href":"https:\/\/www.26yc.com\/fr\/wp-json\/wp\/v2\/media?parent=4717"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.26yc.com\/fr\/wp-json\/wp\/v2\/categories?post=4717"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.26yc.com\/fr\/wp-json\/wp\/v2\/tags?post=4717"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}