Cleanroom vs. Grey Room: What’s the Difference and Why It Matters

In industries such as pharmaceuticals, biotechnology, semiconductor manufacturing, and aerospace, maintaining an environment that ensures product safety, quality, and compliance is crucial. While the term cleanroom is often well-known and understood, many people may not be as familiar with the concept of a grey room. Understanding the difference between a cleanroom and a grey room is important for businesses looking to optimize their operations, adhere to cleanliness standards, and meet industry-specific requirements.

In this blog, we will provide a comprehensive cleanroom vs grey room comparison, exploring the specific functions, cleanliness standards, and operational requirements that distinguish these two types of controlled environments. We will also highlight why choosing the right environment for your industry needs is essential and how Wiselink Group offers tailored cleanroom solutions that adhere to the most stringent standards.

What is a Cleanroom?

A cleanroom is a controlled environment where contaminants, such as dust, airborne microbes, and other pollutants, are carefully managed to ensure that the processes and products within it are protected from contamination. Cleanrooms are used in industries that require ultra-clean environments, where even the slightest contamination can have a major impact on the quality or safety of the final product. Wiselink Group specializes in designing, constructing, and maintaining custom cleanroom solutions that meet the specific needs of industries like pharmaceuticals, medical devices, and semiconductor manufacturing.

Cleanrooms are classified according to cleanliness standards that determine the allowable levels of airborne particles and microbial contamination. The most widely recognized classification system is ISO 14644-1, which sets the standard for the level of particulate contamination permissible in a cleanroom environment. The cleaner the room, the lower the class number, with Class 1 being the cleanest and Class 9 the least stringent.

Key Features of Cleanrooms:

• Particle and Microbial Control: Cleanrooms are equipped with sophisticated air filtration systems, such as HEPA (High-Efficiency Particulate Air) or ULPA (Ultra-Low Penetration Air) filters, that capture airborne particles and microorganisms.
• Controlled Temperature and Humidity: To maintain the integrity of the products, cleanrooms are often equipped with HVAC (Heating, Ventilation, and Air Conditioning) systems that regulate temperature and humidity levels.
• Strict Protocols: Employees working in cleanrooms must follow stringent protocols, such as wearing special gowns and protective gear to minimize contamination from human sources.
• Regular Monitoring and Validation: Cleanrooms are subject to continuous monitoring and periodic validation to ensure compliance with industry standards.

What is a Grey Room?

A grey room, on the other hand, is a more relaxed version of a cleanroom that lacks the strict air cleanliness control and particulate management features of a traditional cleanroom. While grey rooms are designed to provide a controlled environment, they do not adhere to the same stringent cleanliness standards as cleanrooms. Grey rooms are often used in environments where contamination is less critical, or the risks associated with contamination are manageable. These rooms are suitable for applications where moderate contamination control is sufficient, but high levels of sterility are not necessary.

The term “grey room” is often used in various industries to refer to areas that fall somewhere between a cleanroom and a standard manufacturing or working environment. These rooms may still require basic environmental controls, such as ventilation and air filtration, but they generally do not meet the ISO 14644 cleanliness classifications that cleanrooms are subjected to.

Key Features of Grey Rooms:

• Lower Air Cleanliness Standards: Grey rooms typically do not meet the stringent ISO 14644 cleanroom classifications, meaning they allow for higher particle concentrations and microbial contamination.
• Less Strict Protocols: While personnel may still be required to wear protective clothing, the protocols in grey rooms are usually less stringent than those in cleanrooms.
• Basic Environmental Controls: Grey rooms often have basic ventilation and filtration systems to maintain air quality but may not include the advanced air filtration systems like HEPA or ULPA filters found in cleanrooms.
• Lower Cost: Because grey rooms have fewer requirements for air filtration, temperature, and humidity control, they are often less expensive to design, construct, and maintain than cleanrooms.

Cleanroom vs Grey Room: A Detailed Comparison

To better understand the key differences between a cleanroom and a grey room, let’s break down the comparison based on several important factors.

1. Cleanliness Standards

The most significant difference between cleanrooms and grey rooms is the level of cleanliness they provide. Cleanrooms are designed to meet strict cleanliness standards established by regulatory bodies such as the ISO 14644 and GMP (Good Manufacturing Practice). These standards define the maximum allowable levels of airborne particles and microorganisms.

• Cleanrooms: Rely on high-efficiency air filtration systems (e.g., HEPA or ULPA) to remove contaminants from the air. The air cleanliness is classified according to ISO standards, such as ISO 14644-1, and cleanrooms must meet these specifications at all times.
• Grey Rooms: Do not meet the same stringent cleanliness standards as cleanrooms. While some basic air filtration and ventilation systems may be used, grey rooms allow for higher levels of contamination.