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What is a Cleanroom? The All-in-One Guide for Professionals

Written by Encompass | Feb 21, 2025 6:11:39 PM

Many facility managers, engineers, and other industry professionals find themselves needing to design, build, or maintain a cleanroom without a clear understanding of the fundamentals. These contamination-free environments play a critical role in numerous industries, from pharmaceuticals to aerospace and many others. In some of these settings, even microscopic particles or small fluctuations in temperature can compromise product integrity.

Cleanrooms are engineered to maintain ultra-clean conditions by regulating airflow, filtration, humidity, temperature, pressure, and contamination sources. To help you navigate the world of cleanrooms, the Encompass Cleanrooms experts will break down everything you need to know—whether you’re an eager beginner or an experienced professional aiming to deepen your knowledge. 

What is a Cleanroom?

A cleanroom is a meticulously controlled environment designed to maintain specific levels of cleanliness by regulating certain parameters. These spaces are constructed to minimize the presence of airborne particles, microbes, and chemical vapors that could be harmful to sensitive processes and products. Cleanrooms are typically classified based on the permissible number of particles per cubic meter of air, adhering to International Organization for Standardization (ISO) classifications and other standards.

The Connection Between Cleanrooms and Compliance

Oftentimes, facilities need cleanrooms to comply with specific industry standards and regulations. These guiding frameworks ensure cleanrooms achieve the required level of cleanliness for their specific application. At Encompass Cleanrooms, we have extensive experience across many compliance requirements, including the most common:

  • ISO Standards: The ISO 14644 series defines classifications for air cleanliness based on particle concentration, providing a framework for designing and testing cleanrooms. This system defines nine classes, ranging from ISO Class 1 to ISO Class 9, with ISO Class 1 being the most stringent and ISO Class 9 the least. Each class specifies the maximum allowable number of particles per cubic meter for various particle sizes.
  • GMP Standards: Good Manufacturing Practice (GMP) guidelines—particularly relevant in pharmaceutical, biotechnology, and medical device sectors—emphasize maintaining controlled environments to ensure product quality and safety. These standards are overseen by the Food & Drug Administration (FDA) in the United States. There are four classifications: Grades A, B, C, and D, with the first grade being the most stringent. Companies have to undergo a qualification process to demonstrate GMP compliance.

Exploring the Types of Cleanrooms

Selecting the appropriate type of cleanroom depends on factors such as required contamination control levels, flexibility for future modifications, structural permanence, budget constraints, and specific operational needs.

Softwall Cleanrooms

  • Structure: Constructed with clear vinyl curtain walls suspended from an overhead frame, making them lightweight and flexible.
  • ISO Suitability: Typically suitable for ISO Classes 7-8.
  • Airflow and Environmental Control: Utilize less rigid airflow systems with limited temperature and humidity control. Equipped with HEPA or ULPA filters to maintain air cleanliness.
  • Cost: Generally the most affordable cleanroom option.
  • Applications: Commonly used in medical device manufacturing and pharmaceutical industries where flexibility and cost-efficiency are priorities

Hardwall Cleanrooms

  • Structure: Built with solid panels made from materials such as plastic, aluminum, or gypsum, providing a robust and secure enclosure.
  • ISO Suitability: Suitable for all ISO Classes, including more stringent classifications.
  • Airflow and Environmental Control: Offer superior control over airflow, temperature, and humidity, often integrating with HVAC systems and capable of being pressurized for enhanced contamination control.
  • Cost: More expensive than softwall cleanrooms but offer enhanced durability and control.
  • Applications: Ideal for electronics and semiconductor manufacturing, as well as food processing applications requiring stringent contamination control.

Rigidwall Cleanrooms

  • Structure: Constructed with clear, rigid panels, often made of materials like acrylic or polycarbonate, providing a sturdy enclosure with visibility.
  • ISO Suitability: Suitable for ISO Classes 5-8.
  • Airflow and Environmental Control: Align with specific airflow control requirements, offering moderate environmental controls. Utilize HEPA or ULPA filters to maintain required cleanliness levels.
  • Cost: Cost-effective, though generally more expensive than softwall options.
  • Applications: Ideal for processes that benefit from clear visibility, such as monitoring or showcasing operations to stakeholders.

Stick-Built vs. Modular Cleanrooms: What’s the Difference?

When planning a cleanroom, one of the first decisions you’ll make is choosing between stick-built and modular construction methods. Each approach offers distinct advantages and considerations that can significantly impact the design, cost, and functionality of the cleanroom.

Stick-Built Cleanrooms

Stick-built cleanrooms are traditional structures constructed on-site using conventional building materials. They offer high customization and can be tailored to fit unique spatial requirements. However, they typically require longer construction times and may lack the flexibility for easy modification or relocation compared to modular designs.

Modular Cleanrooms

Modular cleanrooms consist of prefabricated components assembled on-site, offering quicker installation and greater flexibility. These cleanrooms can be easily expanded, reconfigured, or relocated to accommodate evolving operational needs. Modular designs are increasingly preferred across industries due to their adaptability and cost-effectiveness.

How Do Cleanrooms Work?

Cleanrooms maintain contamination-free environments through a combination of advanced filtration systems, controlled airflow patterns, environmental monitoring, and adherence to strict operational protocols. Key mechanisms include:

  • Air Filtration: High-Efficiency Particulate Air (HEPA) filters or Ultra-Low Penetration Air (ULPA) filters are employed to remove airborne particles, ensuring a supply of clean air.
  • Airflow Control: Utilization of unidirectional (laminar) or non-unidirectional (turbulent) airflow systems helps in systematically sweeping away contaminants.
  • Environmental Monitoring: Continuous monitoring of temperature, humidity, and particle counts ensures that the cleanroom maintains specified conditions.
  • Operational Protocols: Strict procedures, including gowning protocols and equipment sterilization, are enforced to minimize the introduction of contaminants.

Understanding the Role of Cleanrooms in Specific Industries

While cleanroom environments share fundamental principles across various industries, their design and functionality are often tailored to meet the specific requirements of each sector.

Compounding

In pharmaceutical compounding, cleanrooms provide controlled environments to prevent contamination during the preparation of personalized medications, ensuring patient safety and compliance with regulatory standards.

Semiconductors

The semiconductor industry relies on cleanroom environments to maintain ultra-low levels of particulates, as microscopic contaminants can significantly impact the performance and yield of semiconductor devices.

Aerospace

Aerospace manufacturing utilizes cleanrooms to assemble and test components sensitive to contamination, such as avionics and satellite instrumentation.

Automotive

In the automotive sector, cleanrooms are employed during the production of critical components like sensors and electronic control units, where contamination can affect functionality and safety.

Medical Devices and Packaging

Cleanrooms ensure medical devices and their packaging are produced in environments free from contaminants, safeguarding patient health and meeting stringent regulatory requirements.

Biotechnology

Biotechnology processes—including cell culture and genetic engineering—require cleanroom environments to prevent microbial contamination, ensuring the integrity of biological products and research.

Manufacturing

Various manufacturing industries utilize cleanrooms to control environmental parameters, enhancing product quality and consistency, particularly in the production of high-precision components.

How to Keep Your Cleanroom Environment Contamination-free

Maintaining a contamination-free cleanroom requires strict adherence to cleaning protocols, routine maintenance, and proactive equipment management. Even the most well-designed cleanroom will lose efficiency without proper upkeep.

A robust cleaning protocol should include:

  • Approved Cleaning Solutions & Techniques: Use only cleanroom-approved disinfectants and detergents that do not introduce residues or volatile compounds. Cleaning should follow a top-to-bottom, least-to-most-contaminated approach to prevent cross-contamination.
  • Gowning & Personnel Hygiene: Ensure all personnel follow strict gowning protocols, including donning and doffing procedures that minimize particulate shedding. Frequent glove changes and hand hygiene are also critical.
  • Air Filter Replacement & HVAC Maintenance: HEPA and ULPA filters must be inspected and replaced at manufacturer-recommended intervals. Air pressure differentials should be monitored to maintain airflow integrity.
  • Regular Equipment & Surface Cleaning: All work surfaces, tools, and equipment should be wiped down with lint-free wipes and sterile cleaning solutions at scheduled intervals. High-touch areas should be cleaned more frequently.
  • Scheduled Deep Cleanings & Environmental Monitoring: In addition to daily maintenance, periodic deep cleanings should be performed to eliminate any potential contamination build-up. Environmental monitoring ensures particulate counts remain within acceptable limits.
  • Prompt Repairs & Component Replacements: Any damaged cleanroom panels, seals, or filtration components should be addressed immediately to maintain optimal performance.

At Encompass Cleanrooms, our team of cleanroom experts is highly trained in industry best practices for contamination control. Whether you need assistance with setting up a comprehensive cleaning protocol, training personnel, or sourcing cleanroom-grade supplies, we are here to help you maintain peak performance.

Your Experts in Exceptional Cleanroom Environments

A well-designed cleanroom is only as effective as the expertise behind it. At Encompass Cleanrooms, we bring technical precision and deep industry knowledge to every cleanroom project. Whether you need a new cleanroom designed and constructed, expert consulting on optimizing your existing space, or immediate repairs and equipment upgrades, our team is ready to deliver exceptional solutions. Get in touch with our team.