Clean Room Design and Construction: Environmentally Controlled Area
Introduction
Clean room design is an essential discipline that ensures the creation of controlled environments to carryout the processes inside the cleanroom with stringent levels of cleanliness, air quality, and temperature control. These environments are crucial for industries such as pharmaceuticals, electronics, biotechnology, and more, where even the smallest contaminants can have far-reaching consequences. In this comprehensive guide, we will explore the multifaceted realm of clean room design, covering everything from its significance and types to specifications and the latest technological advancements.
Table of Contents
What Is Clean Room Design?
Clean room design is the meticulous process of creating controlled environments with minimal levels of particulate contamination. These environments are critical for industries to carryout the processes inside the cleanroom that require precision and sterility, including pharmaceuticals, biotechnology, and electronics. Clean room design involves the integration of various elements such as airflow control, filtration, temperature regulation, and specialized equipment to achieve optimal conditions.
The Role of Clean Room Design
Clean room design plays a pivotal role in maintaining the quality and integrity of products and processes. By providing controlled environments with minimal contaminants, clean rooms ensure consistent product quality, regulatory compliance, and safety for both personnel and end-users. They are essential for industries where even minor variations or impurities can lead to significant consequences.
Applications of Clean Room Design
Clean room design finds applications in a wide range of industries, including pharmaceuticals, biotechnology, electronics, healthcare, and more. It is essential wherever precision, sterility, and controlled environments are critical for maintaining product quality and safety.
Types of Clean Room Design
Clean rooms are classified based on the positive pressure & negative pressure environment and also the maximum allowable particle count within a specified cubic meter of air. This classification helps in designing environments suitable for specific processes and applications. Different industries require different levels of pressure gradients & cleanliness class, leading to various clean room classifications.
Positive and Negative Pressure Clean Rooms
Positive pressure clean rooms maintain higher air pressure inside compared to the outside environment. This prevents external contaminants from entering the clean room. Negative pressure clean rooms, on the other hand, keep lower air pressure inside to prevent the escape of potentially hazardous substances, such as pathogens or chemicals.
Clean Room Classification and ACPH Ranges
Clean room classification is a cornerstone of design, ensuring environments meet specific cleanliness levels. ISO standards define classes based on airborne particle count per cubic meter. These classes range from ISO Class 1 (most stringent) to ISO Class 9 (least stringent), each suited for diverse industries.
One crucial metric in clean room design is Air Changes Per Hour (ACPH). ACPH represents the number of times the air within the clean room is replaced with fresh air every hour. This metric guarantees optimal air quality, crucial for preventing contamination and maintaining process integrity.
The relationship between clean room classification and ACPH is vital. Higher classification demands more frequent air changes to meet stringent standards. For instance, ISO Class 1 clean rooms require higher ACPH compared to ISO Class 9 clean rooms.
Understanding this relationship ensures clean room designs align with industry requirements, optimizing efficiency and contamination control. Precision in clean room classification and ACPH ranges contributes significantly to the success of controlled environments. However; Air-change rates do not define cleanliness classes and should be calculated as air-volume flow according to “Source-Strenght” (ISO14644-4:2022) (#8.)
- ISO Class 1: Less than 1 particle/ft³ of 0.5µm size, ACPH Range: 200-600
- ISO Class 5: Less than 100 particles/ft³ of 0.5µm size, ACPH Range: 60-80
- ISO Class 7: Less than 10,000 particles/ft³ of 0.5µm size, ACPH Range: 40-60
- ISO Class 8: Less than 100,000 particles/ft³ of 0.5µm size, ACPH Range: 25-40
Clean Room Design Specifications
Clean room design specifications include requirements for cleanliness levels, temperature control, humidity control, airflow quantity & patterns, and filtration efficiency. These specifications are tailored to the specific needs of the industry and the processes carried out within the clean room.
- Airflow: Direction and speed to control particle movement.
- Temperature & Humidity: Maintaining stability for product integrity.
- Filtration: HEPA and ULPA filters for air purification.
- Pressure Differentials: Preventing contamination by regulating air movement.
- Surfaces & Materials: Non-porous, easy-to-clean surfaces.
Components of Clean Room Design
Key components of clean room design include following but not limited specialized equipment requirement for specific processes such as
- HVAC Systems: Maintain temperature and humidity with temperature, humidity and pressure control devices and systems.
- Air Handling Units (AHUs): Regulate air supply quantity and filtration as per the cleanliness class.
- HEPA/ULPA Filters: Remove particles from the air.
- Cleanroom Walls, Ceilings & Flooring materials: Seamless, smooth surfaces.
- Air Showers & Pass Boxes: Entry and exit decontamination.
Special AHUs and Smart Controls in Clean Room Design
Clean room design often involves specialized Air Handling Units (AHUs) equipped with HEPA or ULPA filters. These AHUs ensure precise temperature and humidity control while providing a consistent flow of clean air. Smart controls and automation technologies further enhance clean room performance by allowing real-time monitoring and adjustments.
Wall and Ceiling Panels in Clean Room Design
Wall and ceiling panels used in clean room design are designed to be smooth, non-porous, and easy to clean. They prevent particle shedding and microbial growth, maintaining the desired cleanliness levels. These panels are often made from materials like stainless steel, aluminum, or specialized plastics, depending on the industry requirements.
HEPA and ULPA Filter Specifications
High-Efficiency Particulate Air (HEPA) and Ultra-Low Penetration Air (ULPA) filters are crucial components in clean room design. These filters remove particles as small as 0.3µm and 0.12µm, respectively. Filter efficiency is expressed as a percentage, and HEPA filters typically have an efficiency of 99.97% for 0.3µm particles, while ULPA filters can achieve up to 99.9995% efficiency.
Return Air Risers in Clean Room Design
Return air risers are essential components in clean room design that facilitate the proper circulation of air. These risers ensure that contaminated air is effectively removed from the controlled environment, contributing to the maintenance of clean air quality.
Advantages & Disadvantages of Clean Room Design
Advantages of Clean Room Design:
- Ensures product quality and reliability
- Prevents contamination-related issues
- Compliance with regulatory standards
- Enhances worker and environmental safety
- Facilitates research and development
Disadvantages of Clean Room Design:
- High initial and operational costs
- Complex maintenance requirements
- Stringent personnel protocols
- Limitations on process scale-up
Latest Technologies in Clean Room Design
The field of clean room design has witnessed significant technological advancements. These include smart sensors for real-time monitoring, advanced filtration systems, robotics for contamination-free handling, and data analytics for process optimization. Latest cleanroom technologies include intelligent air volume control depending on particle concentration.
Clean Room Design Codes & Standards
Clean room design adheres to various industry standards and codes. These standards ensure consistency and quality across different clean room facilities. FDA regulations for pharmaceuticals, and semiconductor industry standards for electronics manufacturing.
- ISO 14644: Particle cleanliness classification.
- GMP (Good Manufacturing Practices): Regulatory guidelines for pharmaceuticals.
- EN 1822: Testing and classification of HEPA and ULPA filters.
Designing and Installing Clean Room Design
Designing and installing a clean room involves careful planning, collaboration with architects and engineers, selection of suitable materials, integration of HVAC systems, installation of filtration and ventilation systems, and compliance with regulatory requirements. Proper installation ensures the achievement of the desired cleanliness levels.
- Layout Planning: Defining zones, flow, and equipment placement.
- HVAC Design: Ensuring precise temperature, relative humidity, differential pressures, cleanliness classification and airflow control.
- Materials Selection: Choosing cleanable, non-shedding surfaces.
- Validation & Qualification: Testing and certifying or documentation of clean room performance.
Clean Room Validation and Documentation
Clean room validation is a critical step to ensure that the designed clean room meets the specified cleanliness levels and performance criteria. It involves various tests, including particle count measurements, airflow velocity assessments, and pressure differential checks. Documentation of clean room validation is essential for compliance with regulatory standards and quality assurance.
Testing, Adjusting & Balancing in Clean Room Design
After installation, clean rooms undergo rigorous testing to ensure that they meet the specified cleanliness levels, temperature, and humidity requirements. The process involves adjusting and balancing HVAC systems, validating filtration efficiency, and conducting particle count measurements.
Controlling Noise & Vibration in Clean Room Design
Noise and vibration control is essential to maintaining a stable and controlled environment within the clean room. Specialized noise insulation materials, vibration isolation techniques, and well-designed HVAC systems contribute to minimizing noise and vibration disturbances.
Clean Room Design Manufacturers and Sub-components
Several manufacturers specialize in providing clean room design solutions, including HVAC equipment, filtration systems, modular clean room components, wall panels, flooring materials, and specialized clean room equipment. These manufacturers play a crucial role in supplying the components necessary for creating controlled environments.
Spare Parts & Maintenance for Clean Room Design
Regular maintenance of clean rooms is vital to ensuring their ongoing performance and adherence to cleanliness standards. Maintenance involves the replacement of filters, calibration of sensors, monitoring of HVAC systems, and addressing any issues that may arise to prevent contamination risks.
Conclusion
Clean room design stands as a testament to human ingenuity and technological innovation. Through meticulous planning, sophisticated equipment, and stringent protocols, clean rooms empower industries to achieve unparalleled levels of precision and quality. From pharmaceuticals to electronics, the impact of clean room design reverberates across diverse sectors, safeguarding both products and people.
Sorry, but this article does not correspond to the current state of the art.
e.g.: cleanliness classes are not specified by air change rates, the US FED Std 209e was superseded in 2001 by ISO14644.