{"id":6187,"date":"2026-09-26T14:50:53","date_gmt":"2026-09-26T06:50:53","guid":{"rendered":"https:\/\/www.bacintl.com\/?p=6187"},"modified":"2026-09-28T08:25:21","modified_gmt":"2026-09-28T00:25:21","slug":"laminar-flow-pass-box-vs-air-shower-pass-box-selection-guide-for-different-cleanroom-classes","status":"publish","type":"post","link":"https:\/\/www.bacintl.com\/fr\/laminar-flow-pass-box-vs-air-shower-pass-box-selection-guide-for-different-cleanroom-classes\/","title":{"rendered":"Laminar Flow Pass Box vs Air Shower Pass Box: Selection Guide for Different Cleanroom Classes"},"content":{"rendered":"

\"\"<\/p>\n

1. Differences in Core Working Principles<\/strong><\/p>\n

Air Shower Pass Box<\/strong><\/a><\/p>\n

An air shower pass box is equipped with a high-pressure fan and nozzles. After materials are placed in the cavity and both doors are closed, high-speed clean air jets the surface of materials from multiple angles to blow off loose dust particles attached to the outer packaging of materials. The separated dust is exhausted out of the cavity along with airflow, reducing contaminants brought into high-grade clean areas. The air shower pass box removes only loose dust on exposed material surfaces by high-speed purging. It cannot continuously maintain a clean environment inside the cavity.<\/p>\n

Bo\u00eete de passage \u00e0 flux laminaire<\/strong><\/a><\/p>\n

A laminar flow pass box is fitted with a HEPA filter on the top. During operation, vertical unidirectional laminar flow is generated to continuously supply clean air inside the cavity and stably control particle concentration. Throughout material transfer, the cavity maintains a stable cleanliness level, restraining particle accumulation and secondary dust emission, so as to realize clean transfer of materials between two clean rooms. The laminar flow pass box maintains a clean environment inside the cavity via continuous laminar air supply. Its core function is to guarantee the cleanliness of the cavity space, rather than purging dust on material surfaces.<\/p>\n

\"\"<\/p>\n

2. Comparison of Basic Characteristics<\/strong><\/p>\n

    \n
  1. \n

    Cleanliness Maintenance Capacity<\/strong> Air Shower Pass Box: After air shower completion, there is no continuous clean air supply. Particle concentration inside the cavity gradually rises. The cavity itself cannot maintain a stable cleanliness level, suitable only as dust removal pretreatment equipment. Laminar Flow Pass Box: Continuous unidirectional laminar flow runs after startup. The cavity can steadily reach Grade A\/B cleanliness. The clean state of the cavity resists short-term disturbance from dust brought in by materials, acting as a clean buffer space.<\/p>\n<\/li>\n

  2. \n

    Focus of Pollution Control<\/strong> Air Shower Pass Box: Removes loose dust on the outer packaging of materials, targeting dust introduced by incoming materials. It cannot eliminate microorganisms or suppress secondary diffusion of particles stirred up by purging. Laminar Flow Pass Box: Controls suspended particles in the cavity space and reduces particle sedimentation during material transfer. Models compatible with VHP sterilization can be applied to scenarios with strict microbial control requirements.<\/p>\n<\/li>\n

  3. \n

    Noise & Energy Consumption<\/strong> Air Shower Pass Box: High fan pressure and jet airflow lead to relatively high operating noise. Each air shower has a fixed countdown time, resulting in higher energy consumption under frequent use. Laminar Flow Pass Box: The fan runs smoothly with lower noise. It can operate continuously for a long time, ideal for processes requiring uninterrupted material transfer.<\/p>\n<\/li>\n

  4. \n

    Operation Procedure<\/strong> Air Shower Pass Box: Load materials \u2192 Close doors \u2192 Start air shower countdown \u2192 Complete air shower \u2192 Open door and take materials. Each material transfer takes a longer time. Laminar Flow Pass Box: Turn on laminar flow, confirm cavity cleanliness, then complete cross-area material transfer. No purging waiting countdown is required, achieving higher transfer efficiency.<\/p>\n<\/li>\n<\/ol>\n

    3. Selection Guide by Cleanroom Grade<\/strong><\/p>\n

    Grade D Cleanroom (General clean areas: food, cosmetics, ordinary packaging workshops)<\/strong><\/p>\n

    Scenario features: Moderate requirements for suspended particles and microorganisms. Materials are mostly raw materials and packaging with intact outer packaging. The main risk is loose dust on outer packaging entering the clean area. Recommended: Air Shower Pass Box<\/strong> When materials enter Grade D clean areas from non-clean areas, air shower purging removes loose dust on outer packaging to reduce basic dust ingress risk. Note: Do not use air shower pass boxes for open, dust-prone powder materials. High-speed airflow will stir up powder and cause secondary contamination inside the cavity.<\/p>\n

    Grade C Cleanroom (Pharmaceutical compounding, intermediate formulation processes, lithium material pretreatment)<\/p>\n

    Scenario features: Higher requirements for particles and microorganisms. Material transfer frequency is high, and some material containers are semi-open, where airflow disturbance to materials is prohibited. Recommended: Laminar Flow Pass Box; Air shower pass box is not recommended.<\/strong> High-speed air shower airflow may disturb materials inside containers and stir up particles, causing cross-contamination. Continuous unidirectional airflow of laminar flow pass boxes keeps the cavity clean without strong airflow impact on materials. If materials enter Grade C from non-clean areas with heavy dust on outer packaging, independent air shower dust removal can be added at the front end before materials are transferred into Grade C via a laminar flow pass box.<\/p>\n

    Grade A\/B High-Grade Cleanroom (Sterile pharmaceutical filling, biological laboratories, semiconductor wafers)<\/strong><\/p>\n

    Scenario features: Strict control over suspended particles and microorganisms, high-risk clean areas where dust emission and airflow disturbance are strictly forbidden. Recommended: Laminar Flow Pass Box (VHP sterilization version optional)<\/strong> Air shower pass boxes are not applicable. Turbulence generated by air shower purging keeps particles suspended, which can easily contaminate Grade A\/B areas. The cavity of a laminar flow pass box maintains unidirectional clean airflow continuously to achieve Grade A cleanliness. For sterile transfer, a VHP vaporized hydrogen peroxide port can be configured for cavity sterilization, complying with EU GMP Annex 1 sterile requirements.<\/p>\n

    General Principles for Cross-Grade Transfer between Cleanrooms<\/strong><\/p>\n

      \n
    • \n

      Low cleanliness grade area \u2192 High cleanliness grade area: Prioritize dust carried by materials. If outer packaging has heavy dust, air shower pretreatment can be arranged at the front end. If materials must not be disturbed by airflow, directly select laminar flow pass boxes.<\/p>\n<\/li>\n

    • \n

      High cleanliness grade area \u2192 Low cleanliness grade area: Ordinary sealed pass boxes are generally acceptable. If materials from high-grade areas are open samples or sterile products, laminar flow pass boxes are still recommended to prevent reverse inflow of air from low-grade areas and material contamination.<\/p>\n<\/li>\n<\/ul>\n

      4. Key Pitfalls to Avoid in Selection<\/strong><\/p>\n

      \"\"<\/p>\n

        \n
      1. \n

        Do not treat air shower pass boxes as clean buffer equipment for high-grade cleanrooms. Air shower only blows loose dust and cannot maintain cavity cleanliness. It cannot replace laminar flow pass boxes for Grade A\/B areas.<\/p>\n<\/li>\n

      2. \n

        Air shower pass boxes are strictly prohibited for powder materials. High-speed airflow disperses powder, causing dust accumulation inside the cavity and persistent contamination risks during long-term operation.<\/p>\n<\/li>\n

      3. \n

        Regular PAO leak testing shall be performed for laminar flow pass boxes to verify intact HEPA filters; otherwise, the cavity cleanliness cannot meet standards. For air shower pass boxes, nozzles and fans shall be inspected regularly to guarantee normal purging airflow.<\/p>\n<\/li>\n

      4. \n

        Distinguish sterilization requirements: Air shower only removes dust with no sterilization capability. For sterile scenarios, laminar flow pass boxes compatible with VHP are required.<\/p>\n<\/li>\n<\/ol>\n

        5. Summary<\/strong><\/p>\n

        The core value of air shower pass boxes is purging loose dust on material outer packaging. Its advantage lies in cost-effective surface dust removal, suitable for transferring solid molded materials from non-clean areas into Grade D cleanrooms. Its limitation is turbulence and dust stirring, so it cannot be used for open material scenarios in Grade A\/B\/C areas.<\/p>\n

        The core value of laminar flow pass boxes is maintaining stable cleanliness inside the cavity without strong airflow disturbance. It is applicable to Grade C, Grade A\/B and other high-grade clean areas. It is the preferred option for sterile, powder and precision material transfer, and can be equipped with sterilization functions to meet specifications of pharmaceutical and biological industries.<\/p>\n

        When selecting equipment for cleanroom projects, cost alone shall not be the only consideration. Cleanliness grade, material form, transfer frequency and microbial control requirements shall be comprehensively evaluated to select the corresponding pass box type, so as to steadily control cross-contamination risks brought by material transfer between different areas.<\/p>","protected":false},"excerpt":{"rendered":"

        Material transfer in cleanrooms is critical for cross-contamination control. As isolation equipment for areas of differing cleanliness, pass boxes are mainly divided into laminar flow pass boxes and air shower pass boxes. Many cleanroom projects confuse these two types during solution selection. Improper selection will raise the risk of particle contamination in clean areas, and may even fail to meet GMP, ISO14644 and other cleanroom standards. Combined with cleanroom classification, this paper compares the principles, features and applicable scenarios of the two types of pass boxes to provide references for project selection.<\/p>","protected":false},"author":3,"featured_media":6188,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[92],"tags":[],"class_list":["post-6187","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\/6187","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\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/comments?post=6187"}],"version-history":[{"count":2,"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/posts\/6187\/revisions"}],"predecessor-version":[{"id":6192,"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/posts\/6187\/revisions\/6192"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/media\/6188"}],"wp:attachment":[{"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/media?parent=6187"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/categories?post=6187"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bacintl.com\/fr\/wp-json\/wp\/v2\/tags?post=6187"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}