Air Purification

The use of clean rooms for sterilization and air purification is a global practice that has expanded with new technologies, increasing expectations for safety in traditional sectors like pharmaceuticals, and expanding applications in industries like nanotechnology. However, each sector and jurisdiction can have varying requirements. This is clearly demonstrated by ISO 14644 – Cleanrooms and associated controlled environments, which provides nine levels of classification for clean rooms (each with a magnitude difference in particle concentrations). What can be considered a “clean room” in one jurisdiction or sector may be considered vastly above or below a standard or regulation in another sector. So, it is important to understand what are the microbial limits for clean rooms in Canada or neighboring jurisdictions like the United States, and therefore what air purification you will need to meet the microbial limit.

Canadian Microbial Limits for Clean Rooms 

Canadian requirements for microbial limits and clean room conditions are determined by the Health Canada through the Food and Drug Act and the embedded regulations. Clean room requirements are described in Food and Drug Regulations (C.R.C., c. 870). Division 2 for Good Manufacturing Practices includes a definition of Sterile Products which requires manufacturing in separate and enclosed areas under the supervision of personnel trained in microbiology by a method scientifically proven to ensure sterility. Note this does not explicitly state the need for a clean room although a clean room is an obvious way to meet this definition.

 

It is not until a supporting document to the Canadian regulation that clean rooms are explained. The Good Manufacturing Practices Guide for Drug Products (GUI-0001) includes an annex specific to clean rooms and other sterile manufacturing requirements. Here, Health Canada defines four types of clean rooms (note this differs from the ISO standard which uses 9 definitions). However, Health Canada references the equivalent ISO standard and also requires the use of ISO methods for sampling and demonstrating clean room conditions. Health Canada also takes a nuanced approach by distinguishing clean room limits when the facility is “at rest” versus when operations are ongoing. The four levels of microbial limits for clean rooms in Canada are:

 

  • Grade A – Limits of 3,520 particles per cubic meter with a size of 0.5μm or greater.
  • Grade B – Has the same limits of 3,520 particles per cubic meter with a size of 0.5μm or greater as Grade A, but allows for a higher tabulated size (20 in Grade A vs 29 in Grade B). This is equivalent in concentration and size to the ISO-5 standard of ISO 14644.
  • Grade C – Limits of 352,000 particles per cubic meter with a size of 0.5μm or greater. This is equivalent to the ISO-7 standard.
  • Grade D – Limits of 3,520,000 particles per cubic meter with a size of 0.5μm or greater. This is equivalent to the ISO-8 standard. 

American Microbial Limits for Clean Rooms

Aeroex also supports American industries and suppliers subject to American regulations. Those familiar with the Canadian system of regulation will see similarities to the American counterpart. Per the Houston Chronicle’s small business guide, clean room requirements set by the Food and Drug Administration are provided through the Current Good Manufacturing Practices series of regulations. Specifically, Code of Regulation 210 and 211 provide requirements for the production of sterile products, notably for:

 

  • Equipment for control over air pressure, micro-organisms, dust, and humidity.
  • Air filtration systems, including prefilters and particulate matter air filters.

 

This set of regulations provides the “overhead” requirements. Additional requirements are typically attached to individual product approvals. 

 

Beyond these regulatory requirements, Aeroex understands that clean rooms can have varying requirements and challenges for different types of industry applications. Read more here to learn how we are considering and tackling these applications. 

How to meet the Canadian Microbial Limits for Clean Rooms

The Air-Fit by Aeroex is a ceiling-mounted fan filtration unit that delivers air circulation with a centrifugal fan and filtration using HEPA filters to meet all clean room standards. The use of HEPA filters guarantees an efficiency rating of 99.99% for particles as small as 0.3 μm, delivering high volumes of HEPA filtered air to your clean room! The Air-Fit should be incorporated into a clean room design for a given standard of air purification, depending on the desired or regulated microbial limits. It is notable from the above discussion that Canada uses a 0.5um particle size threshold, whereas some industries in the United States only go to a 1.0um particle size. The Air-Fit is equipped to exceed Canadian standards by filtering particles as small as 0.3 μm (there is evidence HEPA is effective for smaller particles than this too but this is not guaranteed). 

 

Given the efficiency and particle size threshold of the Air-Fit, Canadian standards for clean rooms can be achieved. The deployment method of the Air-Fit will depend on the size of the facility and required air handling. Aeroex offers different sizes of units ranging from 500 to 1000 cubic feet per minute of capacity and can incorporate multiple units in a series to fully augment your existing mechanical ventilation system. A central control panel is provided in these instances to allow you to monitor and configure multiple units simultaneously.

Ready to Help You Meet Microbial Limits for Clean Rooms in Canada

All our Aeroex units are designed and manufactured in Canada. We support a wide range of Canadian industries and value our local partners. Aeroex is committed to meeting your regulated requirements in a way that provides you the maximum value. If you are seeking a partner in clean room air purification, contact Aeroex today to help us understand your unique needs.