Latest company case about Guangzhou Cleanroom Construction Co., Ltd. Certifications

Pass box serve as critical logistics channels between clean and general areas in dairy production, with their hygiene management directly impacting product safety. Below are key standards based on industry practices:

1. Material Selection

• Main Body: Constructed with food-grade stainless steel (e.g., 304 or higher) for non-toxic, anti-corrosive, and easy-to-clean properties, minimizing contamination risks from material degradation.
• Sealing Materials: Use food-grade rubber/silicone seals that are odorless, anti-aging, and chemically stable to ensure airtightness and prevent chemical reactions with dairy products.
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2. Structural Design

• Smooth Interior: Simple, seamless surfaces with rounded corners (R≥5mm) to eliminate hygienic dead zones and facilitate cleaning, reducing microbial adhesion.
• Airtightness & Interlock: Equipped with sealed doors/air curtains and interlocking systems to prevent cross-contamination by ensuring only one door opens at a time, maintaining pressure stability between zones.
• Optimal Size: Designed based on the largest item dimensions to avoid redundant space, balancing functionality and energy efficiency.
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3. Cleaning & Disinfection

• Daily Cleaning: Wipe interiors with neutral food-grade detergents after production and before/after each use to remove residues and prevent cross-contamination.
• Periodic Disinfection: Weekly deep disinfection using UV light (≥30 minutes) or food-safe disinfectants (e.g., quaternary ammonium, peracetic acid), following a "from inside-out, top-down" order. Validate disinfectant compatibility with materials.
• Emergency Treatment: Immediate disinfection (including ozone if needed) after transferring high-risk items (e.g., raw material packaging) to control microbial risks promptly.
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4. Air Purification

• HEPA Filtration: Install HEPA filters (≥99.97%@0.3μm) in Class A/B clean zones, ensuring airtight installation to prevent unfiltered bypass in critical areas.
• Pressure Control: Maintain directional pressure (positive/negative) via sensors and valves to ensure airflow from clean to less clean areas, with daily pressure monitoring and calibration.
• Maintenance: Replace HEPA filters every 1–2 years or when resistance increases by 50%, followed by integrity testing to ensure efficiency.

5. Microbial Monitoring

• Routine Testing: Quarterly sampling of surfaces, air, and contact points (e.g., door handles) for microbial load (e.g., sedimentation bacteria ≤5CFU/dish・30min) per GB 4789.2 standards.
• Non-Compliance Response: Immediate enhanced disinfection and source tracing (e.g., seal failure, filter leaks) if results exceed limits, re-approving use only after passing retests.
• Preventive Measures: Prohibit storing non-production items, check packaging integrity before transfer, and train operators to reduce human-induced contamination.

By integrating material selection, structural design, cleaning, air purification, and microbial control, Pass box maintain controlled cleanliness, ensuring a safe environment for dairy production.