Pass Box

A static pass box is a simple, sealed chamber with only interlocking doors-no airflow system-used for transferring materials between areas sharing the same cleanliness class (e.g., ISO 7 to ISO 7). It relies on door interlocks to prevent cross-contamination and maintains sterility mostly via UV lamps. A semi-active pass box adds a mild HEPA-filtered airflow—such as a laminar fan-to create a clean microenvironment, useful when transferring from slightly different classification zones. In contrast, a dynamic pass box is fully equipped with HEPA/ULPA filters, blowers, pressure gauges, and automated controls. This model actively purges particles, maintains positive pressure, uses UV or Xenon sterilization, and is suitable for crossing cleanroom grades or handling sensitive materials-mimicking airlock behavior in critical cleanroom workflows.

Labtron Pass Boxes can be extensively tailored for structural and functional needs. Common customizations include internal dimensions, material choice (SS 304/316 stainless steel, coated steel), and interlock mechanisms (mechanical vs. electromagnetic). Users may also select sterilization types (UV C or Xenon lamps), filtration efficiency (HEPA H13/H14 or ULPA), and integrate touchscreen PLC controls, pressure/airflow sensors, or interface with BMS/SCADA systems. Additional options include barcode/RFID readers, auto-sliding glass doors, alarms, and mirrored interiors. This level of customization allows users to ensure compliance with ISO 14644, GMP, and other regulatory standards, while accommodating unique workflows and ergonomic layouts.

Every Pass Box includes mechanical or electronic interlock systems that physically or electronically prevent both doors from opening simultaneously, thus stopping unfiltered airflow between adjacent zones. Mechanical interlocks rely on physical latches or rods, offering reliable, low-maintenance operation. Electronic interlocks incorporate solenoids or electromagnetic locks, often paired with LED indicators signaling door status and alerts if misuse occurs. These systems frequently include fail-safe fallback and audible warnings, reinforcing user compliance and safeguarding cleanroom integrity at every transfer step.

Labtron supplies premium xenon light pass box. Effective Pass Box upkeep demands regular inspection and cleaning. Daily procedures include wiping down all surfaces with IPA or neutral disinfectant. Weekly, UV lamp operation and hour meters should be checked—UV bulbs often require replacement after ~3,000–4,000 operational hours. Monthly, test door interlocks and ensure gasket integrity. Dynamic models require HEPA/ULPA filters to be integrity tested and replaced every 6–12 months, and pre-filters more frequently. Additionally, monitor blower performance and differential pressure to maintain correct airflow and sterilization efficacy.

In static UV-C lamp units, sterilization typically lasts 5–15 minutes, depending on bulb wattage, internal load, and target microbial reduction. Conversely, Xenon flash systems provide rapid broad-spectrum sterilization in just 5 to 20 seconds, achieving microbial and spore kill without residue. Although Xenon offers speed and efficiency, static UV boxes remain suitable for routine hygiene in lower-risk scenarios. Selection should align with required validation speed, cycle frequency, and microbiological risk level to balance throughput and compliance.