I. What is a VHP Pass Box?

The VHP pass box, formally known as the vaporized hydrogen peroxide sterilization pass box, is a high-end cleanroom pass box that integrates room-temperature gaseous sterilization, cleanroom airflow circulation, and dual-door interlocking protection. Unlike conventional UV or ozone transfer cabinets, it enables LOG6-level high-efficiency sterilization, effectively eliminating all types of microorganisms—including bacteria, fungi, viruses, and spores. It is primarily used for the sterile transfer of materials and instruments between different cleanroom zones, thereby preventing cross-contamination between zones; it serves as a core purification component in pharmaceutical, biotechnological research, medical, and electronic cleanrooms.

II. The core operating principle of the VHP pass box

The VHP pass box utilizes the low-temperature sterilization technology of vaporized hydrogen peroxide (VHP), combined with a sealed circulation system and residual gas treatment system; it operates throughout the entire process at room temperature without causing high-temperature damage, features an automated closed-loop workflow consisting of four core steps, ensures stable operation, and guarantees complete sterilization without dead zones:

1. Pre-treatment dehumidification: Upon startup, the equipment automatically adjusts its internal temperature and humidity to optimize the environment within the sealed chamber, preventing water vapor condensation from compromising the sterilization efficacy and laying the foundation for the uniform diffusion of gaseous hydrogen peroxide.

2. Vaporized Sterilization: A built-in dedicated generator subjects 30%–35% concentration liquid hydrogen peroxide to high-temperature flash evaporation, converting it into uniformly dispersed gaseous hydrogen peroxide. The highly active hydrogen peroxide molecules penetrate material crevices and equipment surfaces, disrupting the proteins, cell membranes, and DNA structures of microorganisms, thereby completely inactivating all types of stubborn microorganisms and achieving comprehensive sterilization with no dead zones.

3. Sealed pressure-based sterilization: During the sterilization process, the equipment remains in a sealed state; a dual-door electronic-mechanical interlock system is employed to completely prevent steam leakage upon door opening or ingress of external contaminants, thereby maintaining a stable sterilization concentration and ensuring that the sterilization process meets all required standards.

4. Residual gas decomposition and evacuation: After sterilization is complete, the system activates the catalytic decomposition module, which rapidly decomposes any remaining hydrogen peroxide gas into water and oxygen; this process leaves no chemical residues or secondary pollution. Once compliance with regulatory standards is confirmed, the equipment will be unlocked, allowing normal loading and unloading of materials.

The entire sterilization process features a short cycle time and high efficiency, with full automated control that requires no manual intervention, making it suitable for a wide range of high-cleanliness production and research applications.

III. Key advantages of  VHP pass box

• High sterilization efficacy: achieves a LOG6-level sterilization effect, thoroughly eliminating stubborn microorganisms such as bacterial spores and viruses—far exceeding the capabilities of conventional disinfection methods;

• Ambient-temperature non-destructive sterilization: The entire process operates at low temperatures, ensuring that sensitive items such as precision instruments, packaging materials, and plastic components—those not tolerant of high temperatures—are not damaged;

• No residue ensures greater safety: after sterilization, the residual gas is completely decomposed into water and oxygen—non-toxic and harmless—complying with cleanroom environmental protection standards;

• Cross-contamination prevention: The dual-door interlocking design prevents direct access between high-and low-clean zones, thereby blocking cross-zone contamination at its source;

• Wide compatibility: compatible with a variety of dry and clean materials and equipment; features stable operation and complies with GMP and biosafety laboratory standards.

IV. Main Application Scenarios for VHP Pass Box

1. Biopharmaceutical Industry (Core Application Scenarios)

This equipment is essential for sterile pharmaceutical manufacturing workshops and formulation workshops, offering perfect compliance with GMP certification requirements. It is primarily designed for the sterile transfer of raw materials, excipients, pharmaceutical packaging materials, laboratory instruments, and testing equipment from general areas and low-cleanliness zones to Class A/B high-cleanliness zones, thereby preventing microbial contamination of the sterile production line via these materials and ensuring that drug production quality remains fully compliant with regulatory standards.

2. Biosafety Laboratory

Designed for BSL-2 and BSL-3 biosafety laboratories, this system is used for cross-zone transfer of viral samples, cell cultures, laboratory consumables, and testing samples. It effectively prevents the leakage of pathogenic microorganisms, simultaneously eliminates exogenous bacteria from material surfaces, ensures the safety of the experimental environment, and mitigates the risk of experimental cross-contamination and biosecurity hazards.

3. Hospital medical cleanroom environments

It is widely used in operating rooms, sterile wards, central sterile supply departments, and clinical laboratories. It facilitates the sterile transfer of surgical instruments, sterile dressings, laboratory specimens, and medical consumables, thereby reducing the risk of healthcare-associated infections and ensuring a clean and safe environment for medical procedures.

4. Precision Electronic Cleanroom

Designed for production workshops in chip manufacturing, semiconductor fabrication, precision component assembly, optical instrumentation, and related industries, this system enables the cross-cleanroom transfer of components, turnover pallets, packaging materials, and testing tools. It provides both sterilization and dust removal capabilities while preventing high temperatures and chemical reagents from causing damage to precision components, thereby ensuring the required cleanliness class for the precision manufacturing environment of electronic products.

5. Food Testing and Daily Chemicals Cleanroom

In food microbiological testing laboratories, this system is used for the sterilized transfer of food samples and testing equipment to ensure the accuracy and authenticity of test results; in sterile production workshops for daily chemical products, it is employed for the sterile transfer of skincare products, cosmetic raw materials, and packaging materials, thereby complying with sterile production quality control standards.

V. Summary of Common Frequently Asked Questions

Q: What is the difference between a VHP pass box and a standard pass box?

A: Standard pass box only provide dust removal and isolated ventilation functions; their UV and ozone sterilization processes are incomplete and cannot eliminate bacterial spores; in contrast, VHP pass box enable comprehensive high-efficiency sterilization—eliminating dead zones and leaving no residues—making them suitable for high-grade cleanroom environments and compliant with stringent industry regulatory standards.

Q: Can a VHP Pass Box handle all types of items?

A: This is only applicable to materials and containers that are dry, free of oil contamination, and resistant to gaseous hydrogen peroxide; it should not be used for transporting moist, corrosive, flammable, or explosive substances.