Modular Cleanroom Ventilation Requirements

Maintaining modular cleanroom ventilation requirements ensures the environment inside your room remains clean and free from contamination. Proper design, construction, and maintenance of the ventilation system can help you achieve the required air quality and prevent product contamination. Here are some key considerations for designing your cleanroom:

Cleanroom Basics

Cleanrooms are specialized controlled environments used to maintain an exceptionally low level of contamination. Various industries use cleanrooms, including pharmaceuticals, biotechnology, microelectronics, aerospace, and health care. Cleanroom ventilation designs are modified to eliminate contaminants, like dust, airborne microbes, aerosol particles, and chemical vapors, that can affect the quality of products or processes.

Overall, cleanrooms are essential in industries where even small amounts of contamination can significantly impact the quality of products or processes.

The cost of establishing a safe cleanroom can vary depending on several factors, including the following:

• Design and construction: Cleanrooms are built using specialized materials and construction techniques to create an environment that can be easily controlled and maintained. You’ll want to consider the costs of the cleanroom’s walls, ceiling, and floors, which are constructed using non-shedding materials, such as stainless steel or epoxy-coated surfaces, and sealed to prevent the entry of contaminants. Doors and windows are designed to stop contaminants from getting in. A cleanroom is also equipped with specialized ventilation systems that provide filtered air to maintain a positive pressure within the room.
• Room personnel requirements: In addition to the cleanroom ventilation design and construction, maintaining the environment’s cleanliness requires strict protocols for personnel and equipment entering and exiting the cleanroom. This may include changing into specialized cleanroom attire, such as gowns, gloves, hairnets, and face masks, and decontaminating equipment and surfaces before entering the room.
• Equipment: You should also factor in costs for equipment to establish a safe cleanroom, such as laminar flow workstations, fume hoods, cleanroom chairs and specialized lighting. Using an HVAC for a cleanroom is also essential to maintain proper air quality. Professionals can establish cleanroom designs with HVAC systems that include calculations of heat load, airflow rate, pressure drop, and filter efficiency.
• Minimum ventilation requirements: Cleanrooms are typically classified according to the level of cleanliness required, based on the number and size of particles allowed per cubic meter of air. The classification system used is International Organization for Standardization (ISO) 14644-1, which ranges from ISO Class 1or the fewest allowable particles, to ISO Class 9, or the most allowable particles.

It’s also crucial to consider the air change rate when constructing a cleanroom. The air change rate is the number of times the cleanroom’s air volume is exchanged per hour. Air changes per hour for cleanrooms depend on the classification and level of cleanliness required. For example, ISO 7 cleanrooms typically require an air change rate of 20-30 changes per hour, while ISO 5 cleanrooms may require up to 600 changes per hour.

Types of Cleanroom Airflow Patterns

Airflow and filtration options are critical components of cleanroom design, and the type and complexity of these systems can affect the overall cost of establishing a cleanroom. Here are some variations of airflow and filtration options available in cleanrooms:

• Unidirectional airflow: In a unidirectional airflow system, air enters the cleanroom through a series of filters and flows in a straight line at a constant velocity to a designated exhaust point. This creates a laminar flow that helps to prevent contaminants from accumulating on surfaces and in the air.
• Non-unidirectional airflow: In a non-unidirectional airflow system, airflow is not restricted to a single direction but can move freely around the room. This type of airflow is often used in cleanrooms with ISO classes 6 through 9.
• HEPA filtration: High-efficiency particulate air (HEPA) filters are designed to remove particles 0.3 microns or larger. HEPA filters are commonly used in cleanrooms to remove airborne particles and are often required by regulatory agencies.
• ULPA filtration: Ultra-low particulate air (ULPA) filters are similar to HEPA filters but are designed to remove particles smaller than 0.3 microns.
• Positive pressure systems: Cleanrooms are typically designed to maintain a positive pressure, meaning that the air pressure inside the cleanroom is greater than the pressure outside the room. This helps prevent contaminants from getting into the cleanroom.
• Negative pressure systems: Cleanrooms may be designed to maintain a negative pressure, meaning that the air pressure inside the room is lower than the pressure outside the room. It is often used when there is a risk of airborne contaminants escaping the cleanroom.

A cleanroom HVAC system can help maintain a controlled environment with the desired air quality. A cleanroom HVAC system typically includes several components, including ductwork filters and exhaust systems. Cleanroom HVAC design calculations are complex and require the expertise of professionals with experience in cleanroom design and construction.

How to Achieve Cleanroom Airflow Uniformity

Achieving cleanroom airflow uniformity is crucial for maintaining a controlled environment that meets the required air quality standards. When setting up a modular cleanroom, it’s essential to consult an expert in cleanroom design to ensure that the ventilation system meets the requirements for the intended use of the cleanroom.

Here are some steps that can help achieve cleanroom airflow uniformity:

Choose the Right Air Distribution System

As mentioned, various types of air distribution systems are available for cleanrooms, including laminar flow, turbulent flow, and mixed flow systems. Each system has its advantages and disadvantages, and choosing the right one will depend on the cleanroom’s specific requirements and the type of work being performed.

Ensure Proper Placement of Supply and Return Vents

The placement of supply and return vents is critical in achieving airflow uniformity. Supply vents should be placed near the ceiling, and return vents should be placed near the floor. This will create a vertical airflow pattern that prevents contamination from settling on surfaces.

Use Airflow Visualization Techniques

Airflow visualization techniques such as smoke tests or particle imaging velocimetry (PIV) can help identify areas of the cleanroom where airflow is not uniform. These techniques can also help identify sources of turbulence or dead zones.

Maintain Proper Filter Maintenance

Filters play a crucial role in maintaining cleanroom air quality, and ensuring they are clean and functioning correctly is essential. Regular filter maintenance and replacement ensure uniform airflow and contaminant removal.

Prevent Airflow Turbulence

You can achieve airflow uniformity by minimizing, removing and accounting for any factors that might cause turbulence. Ensure your cleanroom airflow patterns accommodate your layout, equipment, furniture and personnel by:

• Keeping large equipment and furniture from blocking fan filter units
• Adjusting equipment with aerodynamic attachments or design features
• Using perforated cleanroom tables to ensure air can pass through uninhibited
• Ensuring personnel do not block airflow within critical zones

Discover the Benefits of Expert Custom Cleanroom Airflow Design

Achieving cleanroom ventilation requirements requires careful planning and design. You can reach the required air quality standards and maintain a controlled environment by determining the cleanroom classification, choosing the right ventilation system, using HEPA filters, and maintaining proper airflow.

Ensure a safe cleanroom ventilation design by hiring experts to design your airflow patterns. Starrco has the tools and experience to create a cleanroom layout that optimizes airflow to meet your requirements. Our design, engineering, and manufacturing experts can craft the cleanroom modules at our facility and deliver them straight to you, ready to assemble and integrate.

To get started, request a free quote today.