Understanding Static and Dynamic Pass Box

Maintaining controlled environments is crucial in various industries, including pharmaceuticals, electronics, and healthcare. Pass boxes are essential tools used to transfer materials between these environments while minimizing contamination risks. But with two main types – static and dynamic – choosing the right one for your needs can be confusing. This blog aims to demystify the differences between static and dynamic pass boxe, helping you understand which one best suits your specific application.

What are Pass Boxes?

Pass boxes are enclosed chambers installed between two rooms. They allow for the safe transfer of materials between these rooms without compromising the environmental conditions on either side. Both static and dynamic pass boxes utilize a double-door interlocking system, ensuring only one door can be opened at a time, preventing direct airflow between the environments.

Static Pass Boxes:

Function: Used to transfer materials between two equally clean environments. For example, transferring tools between two cleanrooms with the same ISO classification.

Operation: Relies on passive air exchange. When one door is opened, the pressure difference between the room and the pass box causes air exchange. This method is suitable for low-risk applications where minimal contamination risks exist.

• Simpler design compared to dynamic pass boxes.
• May not include air filtration or purification systems.
• Often equipped with UV lights for surface disinfection.
• Interlocking doors with LED indicators to ensure only one door is open at a time.

Dynamic Pass Boxes:

Function: Used to transfer materials between an uncontrolled environment (e.g., non-cleanroom) and a controlled environment (e.g., cleanroom). They are also suitable for transfers between environments with different cleanliness levels.

Operation: Employs an active air filtration system to maintain a positive pressure environment within the pass box. This positive pressure prevents contaminated air from entering the controlled environment when transferring items from the uncontrolled side.

• More complex design compared to static pass boxes.
• Outfitted with HEPA filters designed to eliminate airborne pollutants.
• May include purging cycles to further reduce contamination risks.
• Often equipped with pressure gauges to monitor the positive pressure within the pass box.

Choosing the Right Pass Box:

Here are some key factors to consider when choosing between a static and dynamic pass box:

• Cleanliness Levels of Environments: If transferring materials between equally clean environments, a static pass box might suffice. However, for transfers involving uncontrolled environments or rooms with differing cleanliness levels, a dynamic pass box is essential.
• Sensitivity of Materials: Highly sensitive materials requiring a strict contamination-controlled environment, especially during transfer, will benefit from the increased protection offered by a dynamic pass box.
• Efficiency: Dynamic pass boxes generally involve longer transfer times due to purging cycles. If transfer speed is a critical factor, a static pass box might be preferred for low-risk applications within controlled environments.

Additional Considerations:

• Size and capacity: Choose a pass box with appropriate dimensions to accommodate the size and quantity of materials typically transferred.
• Material compatibility: Ensure the pass box is constructed with materials compatible with the cleaning and disinfection procedures used in your facility.
• Regulatory compliance: Ensure the pass box meets any relevant industry standards or regulatory requirements for your application.

Conclusion:

Understanding the differences between Static and daynamic pass box is crucial for selecting the most appropriate equipment for your specific needs. By considering the factors mentioned above, you can make an informed decision that ensures the safe and efficient transfer of materials while maintaining the desired level of environmental control.