Steam sterilizer of the passage type

The Pass-Through Steam Sterilizer is an essential component for maintaining cleanroom integrity in pharmaceutical and medical manufacturing. Its "pass-through" design serves as a sterile barrier between rooms of different cleanliness classes, allowing for the safe transfer and sterilization of garments, instruments, and porous materials.

The system utilizes pressurized saturated steam to ensure rapid and effective microbial lethality, followed by high-performance vacuum drying to ensure materials are ready for immediate use in aseptic zones.

Construction and Operational Features

• Sterilization Chamber: A double-walled pressure vessel. The internal chamber is fabricated from SUS 316L stainless steel with a mirror finish ($Ra \leq 0.4$ μm), providing superior corrosion resistance and ease of sanitation.

• Heating Jacket: The outer shell, made of stainless steel 304, covers the internal chamber to minimize condensation and ensure uniform temperature distribution throughout the cycle.

• Advanced Insulation: An aluminum silicate layer between the chamber and jacket minimizes heat loss and ensures energy efficiency.

• Automated Pass-Through Doors: Equipped with pneumatic sliding or swinging doors featuring inflatable seals. The interlock system prevents both doors from opening simultaneously, preserving the pressure differential between cleanroom zones.

• Sanitary Piping System: Includes sanitary-grade valves, an absolute air filter (0.22 μm) for sterile venting, and a high-efficiency liquid ring vacuum pump for effective air removal and drying.

Technological Cycles

The sterilizer is pre-programmed with specialized cycles to ensure process reliability:

1. Bowie-Dick Test: A standardized cycle (typically $134$ °C for 4 min) to verify the effectiveness of air removal and steam penetration.

2. Vacuum Leak Test: Automatically checks the hermetic integrity of the chamber and piping.

3. Sterilization Cycle: Designed for porous loads (textiles, garments) and hard goods, followed by a pulse-vacuum drying phase.

Control and Safety

The unit is managed by an industrial PLC controller with a high-resolution touchscreen HMI and an integrated thermal printer for batch record documentation. Safety features include:

• Mechanical and Software Interlocks: Doors cannot be opened if the chamber is pressurized or if the temperature is above the safety threshold.

• Emergency Protocols: Automatic cycle termination and venting in the event of utility failure or parameter deviation.

Validation and Compliance

The equipment is designed to meet the most stringent regulatory requirements:

• GMP Annex 11 & GAMP 5: Full validation protocols for automated systems according to ISPE guidelines.

• Data Integrity: Electronic records and secure audit trails for pharmaceutical quality management.

Technical Specifications