A pass box is a sealed chamber with two doors : one opening to a clean room, the other to a less controlled area. It transfers items like tools or samples without letting contaminants like dust or microbes sneak in, protecting the clean room's integrity.
What's the Purpose of a Pass Box?
Clean room cannot afford contamination, as opening a door to pass materials risks introducing particles that could compromise everything. A pass box serves as a buffer, preventing this risk and maintaining the cleanroom's integrity.
You load items from the outside, close the door, and only then can someone inside retrieve them. It cuts human traffic, maintains air pressure, and often includes HEPA filters or UV lights to kill germs. It's about safety and efficiency, keeping your work on track without compromise.
How Does a Pass Box Work?
It's simple but precise. A stainless steel box sits in the wall, with interlocking doors: one must lock before the other opens, stopping dirty air from rushing in. Load an item, shut the outer door, and some models decontaminate with filtered air or UV light. Then the clean side unlocks.
Types of Pass Boxe
- Static Pass Box: Basic models with no airflow, relying solely on physical separation. Ideal for low-risk transfers .
- Dynamic Pass Box: Equipped with HEPA filters and airflow systems to actively decontaminate items. Critical for high-risk environments like pharmaceuticals or semiconductor labs.
- UV Pass Box: Use ultraviolet light to sterilize items during transfer, often combined with airflow systems.
How Do You Choose a Pass Box for Your Clean Room?
Your clean room's ISO rating decides. ISO 7-8 might need just a static pass box. ISO 5-6 demands a dynamic one with filtration. ISO 1-4 may require custom features like air showers. Match the size to your needs, don't skimp or overspend.
How Should You Use a Pass Box?
Place the item in, close the outer door, wait for any sterilization, then open the clean side. Keep it quick, don't store stuff inside. Clean it regularly, and don't force doors open, that breaks the interlock and invites trouble.
FAQS
What's the typical lifespan of a pass box?
With proper care, a well-made pass box can last 10-15 years.
How does the interlocking mechanism in a pass box work?
It's usually electromagnetic or mechanical locks that ensure one door stays shut until the other's closed. Sensors or latches make sure there's no overlap, keeping the clean room safe.
Do I need a professional to install a pass box?
Yes, a pro ensures it's sealed into the wall or floor correctly and the interlock works perfectly, DIY mistakes could leak contamination.
What's the energy consumption of a pass box?
Static ones use almost nothing, just enough for the locks. Dynamic models with filters or UV can pull 100-500 watts, depending on the setup.
What's the typical self-cleaning time for a pass box?
It varies, UV cycles might take 5-15 minutes, while HEPA filtration could run continuously or reset after each use. Check your model's specs.