Expert Guide to Dynamic Pass Box Maintenance and Repair

Dynamic Pass Box: An Integral Cleanroom Tool

A dynamic pass box, also known as a pass-through box or transfer hatch, is an essential piece of equipment in any cleanroom environment. It facilitates the secure and controlled transfer of small items between controlled or classified areas, minimizing contamination risks. By reducing the frequency of door openings in cleanrooms, dynamic pass boxes help maintain desired air pressure and particle levels, crucial for sensitive processes and products.

See more: Working Principle of Dynamic Pass Box

Optimizing Performance: A Comprehensive Maintenance Guide

Like any machinery, dynamic pass boxes require regular maintenance for optimal functionality and longevity. Here's a comprehensive guide to ensure your pass box operates at its peak:

1. Filter Replacement:

• Schedule: Replace the pre-filter every 1-6 months and the HEPA filter every 6-12 months, depending on your environment's cleanliness level. Always shut down the machine during filter changes.
• Quality Control: Regularly (every 2 months) measure the cleanroom's particle count within the pass box area. Discrepancies from required levels suggest potential leaks or worn filters. Replace the HEPA filter if necessary.

2. Disinfection:

Frequency: Sterilize the pass box weekly. Wipe surfaces and the UV lamp with gauze moistened with solvents like alcohol or acetone to maintain cleanliness.

See more: Validating pass box cleanroom

3. HEPA Filter Replacement:

• Airflow Guidance: Ensure proper airflow by aligning the arrow on the new filter with the laminar airflow direction.
• Leak Testing: After replacing the HEPA filter for Pass Box, use a laser particle counter to verify frame sealing integrity.

4. Fan Speed and Air Velocity:

• Optimal Range: Adjust the fan speed to maintain an average air velocity between 0.3m/s and 0.6m/s within the operating area.
• Confirm optimal airflow and cleanliness using a laser particle counter.

5. Safety Precautions:

• Power Shutoff: Always unplug the power cord before performing maintenance or repairs.
• Professional Expertise: Only qualified technicians should handle circuit boards or potentiometer adjustments.

6. Differential Pressure Gauge:

• Accurate Measurements: Understand the gauge's sensitivity to temperature and grid voltage for accurate readings.
• Abnormal Pressure: If the differential pressure deviates from expected values, wait for the fan to stop and restart the pass box. It may automatically reset.

7. HEPA Filter Handling:

• Protect the Filter: During unpacking, handling, and installation, ensure the filter sheet remains intact and undamaged. Avoid touching the filter surface.
• Leak Inspection: Before installation, inspect the new filter under bright light for any transportation-induced leaks. Discard any damaged filters.

By adhering to these guidelines, you can ensure your dynamic pass box remains a reliable and efficient tool in maintaining the integrity and optimal performance of your cleanroom environment.

See more: Validating pass box cleanroom