Enhancing Cleanroom Integrity: The Role of Air Showers and Pass Thrus

Cleanrooms are controlled environments designed to maintain extremely low levels of particulate contamination. Industries such as pharmaceuticals, electronics manufacturing, biotechnology, and aerospace heavily rely on cleanrooms to ensure product quality, safety, and compliance with strict regulations Air showers and pass thrus are essential components of cleanroom infrastructure that help in controlling contamination and maintaining a sterile environment.

What are Air Showers?

An air shower is a self-contained chamber that uses high-velocity, filtered air to remove contaminants from individuals or objects before they enter or exit a cleanroom. It acts as an airlock, creating a barrier between the cleanroom and the external environment, preventing the ingress of particles.

Components of Air Showers

Air showers consist of various components working together to provide efficient contamination control. Let's explore the key components:

Air Shower Chambers

Air shower chambers are typically constructed from stainless steel and feature transparent doors on either side. These chambers are designed to accommodate one or more individuals or objects at a time, depending on the size and configuration. The chamber's interior is equipped with strategically placed air nozzles that direct high-velocity air towards the personnel or objects.

High-Efficiency Air Filters

Air showers incorporate high-efficiency particulate air (HEPA) filters to remove particles as small as 0.3 microns with an efficiency of 99.97%. These filters capture airborne contaminants, ensuring the air blown onto the personnel or objects is clean and free from particles.

Powerful Blowers

The heart of an air shower lies in its powerful blowers that generate high-velocity air streams. These blowers create the necessary force to dislodge and remove contaminants effectively. The airflow is carefully calibrated to ensure optimal particle removal without causing discomfort to the personnel.

Control Panel and Sensors

Air showers feature a control panel that allows users to initiate the decontamination cycle and control various settings. Sensors are strategically placed to detect the presence of individuals or objects and initiate the airflow automatically. These sensors ensure efficient and reliable operation while minimizing energy consumption.

Importance of Air Showers in Cleanrooms

Cleanrooms are critical environments where even the smallest particles can have severe consequences. Here are some key reasons why air showers are vital in maintaining cleanroom integrity:

Contamination Control

Air showers play a crucial role in contamination control by removing loose particles from individuals or objects before they enter the cleanroom. By significantly reducing the particle count, air showers help maintain the desired cleanliness level within the controlled environment.

Worker Safety

Cleanroom personnel may unintentionally carry contaminants on their clothing or body, posing a risk to both themselves and the cleanroom environment Air showers effectively remove these contaminants, ensuring the safety of the workers and preventing cross-contamination.

Product Protection

Many industries, such as semiconductor manufacturing or pharmaceutical production, require a pristine environment to avoid product defects or failures. Air showers contribute to product protection by reducing the risk of contamination, ultimately improving product quality and reliability.

Types of Air Showers

Air showers come in various configurations to suit different cleanroom applications. The two primary types of air showers are personnel air showers and material air showers.

Personnel Air Showers

Personnel air showers are designed for decontaminating individuals before they enter the cleanroom. These air showers feature spacious chambers that can accommodate one or more persons at a time. Personnel air showers are equipped with additional features like overhead LED lights, mirrors, and shoe-cleaning systems to ensure comprehensive decontamination.

Material Air Showers

Material air showers are specifically designed to clean objects or materials before they enter the cleanroom. These air showers are usually smaller in size and feature specialized racks or shelves to hold the materials. Material air showers are commonly used in industries where the cleanliness of incoming materials is critical, such as medical device manufacturing or precision engineering.

What is Pass Thru?

A pass thru, also known as a transfer hatch, is a controlled access portal between two cleanrooms or between a cleanroom and the outside environment. Pass thrus allow the transfer of materials or equipment while minimizing the risk of contamination. They maintain the cleanroom's integrity by preventing direct airflow between the controlled environments.

Types of Pass Thrus

There are different types of pass thrus available, each serving specific purposes. Let's explore the common types:

Mechanical Interlock Pass Thrus

Mechanical interlock pass thrus are the most basic type of pass thrus. They feature interlocked doors on each side, allowing only one door to be opened at a time. This interlocking mechanism prevents cross-contamination by maintaining a physical barrier between the cleanroom and the external environment.

Air Shower Pass Thrus

Air shower pass thrus combine the functionality of air showers and pass thrus These pass thrus are equipped with air shower functionality on one or both sides, ensuring the decontamination of materials or equipment before they enter or exit the cleanroom. Air shower pass thrus are commonly used in environments where the transferred materials need additional decontamination.

Non-Interlocking Pass Thrus

Non-interlocking pass thrus are simpler in design and do not feature interlocked doors. They are commonly used in less critical applications where the risk of contamination transfer is relatively low. Non-interlocking pass thrus offer basic access control while still providing a barrier between the cleanroom and the outside environment.

The Role of Pass Thrus in Cleanroom Design

Pass thrus are an integral part of cleanroom design and play a crucial role in maintaining contamination control. Here are a few ways pass thrus contribute to cleanroom integrity:

Preventing Contamination Transfer

Pass thrus act as a physical barrier that prevents direct airflow between cleanrooms or between cleanrooms and external areas. By maintaining a controlled transfer environment, pass thrus minimize the risk of contamination transfer and ensure the cleanliness of the cleanroom.

Maintaining Positive Pressure

Cleanrooms are often designed with positive pressure differentials to prevent the ingress of contaminants from less controlled areas. Pass thrus help maintain these positive pressure differentials by providing a controlled access point that minimizes the disruption of airflows and prevents the escape of filtered air.

Pass thrus also help in maintaining the integrity of classified areas by restricting access to authorized personnel only, further ensuring contamination control.

Choosing the Right Air Showers and Pass Thrus

When selecting air showers and pass thrus for your cleanroom, several factors need to be considered. Let's take a look at some key considerations:

Maintenance and Cleaning

To ensure the optimal performance and longevity of air showers and pass thrus, regular maintenance and proper cleaning are essential. Here are some guidelines to follow:

Regular Maintenance Procedures

Follow the manufacturer's guidelines for routine maintenance procedures, including filter replacement, blower inspection, and sensor calibration.

Regularly check and clean the air nozzles to ensure unrestricted airflow and effective particle removal.

Inspect the control panel and sensors for any signs of damage or malfunction, and address any issues promptly.

Perform regular airflow measurements and adjust the air shower settings if necessary to maintain the desired airflow velocity.

Cleaning Guidelines

Clean the interior and exterior surfaces of the air shower and pass thru using approved cleaning agents, following the manufacturer's recommendations.

Pay special attention to the doors, door seals, and other areas where contaminants can accumulate.

Ensure that all surfaces are thoroughly dried after cleaning to prevent the growth of microorganisms.

By adhering to proper maintenance and cleaning practices, you can maximize the lifespan of your air showers and pass thrus while ensuring optimal performance in contamination control.

Conclusion

Air showers and pass thrus play a critical role in maintaining contamination control and ensuring the integrity of cleanroom environments. By effectively removing loose particles from individuals and objects, air showers minimize the risk of contamination, protecting both the cleanroom and its occupants. Pass thrus act as an additional barrier, preventing contamination transfer and maintaining positive pressure differentials. Selecting the right air showers and pass thrus, following maintenance procedures, and adhering to cleaning guidelines are essential for optimal performance and longevity.

With the advancements in cleanroom technology, air showers and pass thrus continue to evolve, offering improved efficiency and functionality. By incorporating these specialized equipment into cleanroom design, industries can enhance product quality, worker safety, and regulatory compliance.