Why are Cleanrooms Necessary for Medical Device Manufacturers?

The healthcare industry is known for its high standards and strict regulations that ensure the safety of its sensitive products. The decision to manufacture medical devices means dealing with all of the industry’s attendant regulations. Many regulatory specifications apply across the globe; the specific device classification is scrutinized, careful device records must be kept, and cleanrooms are often needed for the fabrication process.

So, why are cleanrooms a requirement for medical device manufacturing? The short answer is that they reduce contamination within the manufacturing space by filtering the particulates such as dust, airborne organisms, or vaporized article from entering the room. The more expansive answer demands a deeper look into the relevance of cleanrooms to medical manufacturers, the reasons governments require them, and the associated standards.

What are cleanrooms?

Cleanrooms are enclosed spaces where environmental controls are applied to prevent contamination of the manufacturing equipment and materials used in an item’s production. Cleanrooms eliminate contaminants by filtering airborne particulates, utilizing anti-microbial surfaces, and preventing operators from bringing contaminants into the enclosed space in the first place.

The particulate-free environment of a cleanroom also prevents operators working within from transferring infections. The average cleanroom is designed with sanitized entryways and without windows to reduce external airflow. Spaces designated as cleanrooms are also isolated from other parts of a manufacturing facility to reduce the possibility of infectious pathogens infiltrating them.

The importance of cleanrooms to manufacturers

The use of cleanrooms benefits medical device manufacturers in a number of ways. They ensure the safety of both equipment operators and end-users and help manufacturers optimize profitability on a wide scale. The major benefits include:

• Protecting the end-user: Creating medical devices that are devoid of pathogens protects the health of patients and healthcare service providers against biological contamination.
• Protecting the workforce – Some raw materials used in the medical device production cycle produce contaminants that could be hazardous to operators. Cleanrooms protect floor operators using measures such as gowning areas, protective equipment, and air filtration systems to keep the immediate environment safe for personnel.
• Securing medical device certifications – Successfully marketing medical devices on a global scale means manufacturing them in a cleanroom that meets all of the diverse international standards that apply where the device is to be sold. Implementing these international standards gives manufacturers access to a larger customer base, thus increasing profitability.

Requirements for setting up cleanrooms

It is the responsibility of each medical device manufacturer to meet the requirements and standards that apply in the region where their facilities are located. In the United States, the Food and Drug Administration (FDA) sets the rules. In the European Union, the European Medicine Agency and individual agencies within European states share decision-making responsibilities for cleanroom guidelines.

Across the world, International Organization for Standardization (ISO) standards define the most common requirements for building cleanrooms. Many countries accept the ISO standards for their own medical device evaluations. For example, even in the US, the International Standard ISO 14644, which is dedicated to classifying cleanrooms and their air cleanliness requirements, now supersedes the local Federal Standard 209E. Manufacturers must remain vigilant and be able to respond to changing regulations.

The multiplicity of cleanroom requirements across the world means that hundreds of pages of documentation have been dedicated to describing these diverse regulations. However, the most important regulations show up in every country’s requirements. These requirements include:

1. A dedicated cleanroom air monitoring system – Tracking cleanroom air quality is critical if particle thresholds and airflow regulations are to be met over the long term. Putting a monitoring system in place to continuously measure contaminant concentration is a key requirement. The FDA, the European Medicine Agency, and ISO 14644 all outline the need for monitoring systems and documentation of cleanroom conditions.
2. Continuous testing for contaminant particles – Human activity produces large numbers of contaminant particles. The average operator, even if they remain motionless, adds 100,000 0.3 micron particles per minute to a room (and obviously, operators cannot remain motionless while performing their jobs). Mitigating the risks associated with particle-producing activities starts with testing air particles to devise strategies to deal with excess particulates. The necessary air filtration systems will depend on the types and quantities of particles in the workspace.
3. Written procedures for preventing contamination – Generally, medical devices are used in close contact with human skin or vital organs. To ensure manufactured devices do not harm the end-users, contamination prevention measures must be documented and provided to the applicable regulatory agencies. Regulators will expect documentation of these preventative activities both as they apply to the product itself and to the processes used to create it. If the process meets specified guidelines, a commercial certification will then be offered.

Factors to consider when designing a cleanroom

An integrated process that continuously removes contaminants and recycles the air within the enclosed space is central to the design of a cleanroom. Other important factors to consider include:

• Evaluating the layout of the manufacturing floor – An optimized layout must consider asset location, floor traffic, entrance points, and the movement of finished goods from the shop floor. Generally, there should be no more than two entryways; one will usually function as the entry and the other as the exit point at the opposite end of the cleanroom. Limiting the number of entry and exit points reduces pathogen infiltration pathways and helps to manage personnel access to a cleanroom. An optimized layout supports the reduction of shop floor traffic by defining dedicated workstations and walkways for operators while providing a different passageway for raw-material handling systems.

• Determining the required cleanliness classification – Cleanroom classifications, provided by regulatory agencies, are based on the allowable number of particles per unit volume inside the room. For example, a class 100 cleanroom, built for medical device manufacturing, should not exceed 3,500 particles per cubic foot.

• Analyzing cleanroom positive pressure requirements – Maintaining an optimal positive room pressure helps to prevent contaminants from entering a cleanroom. Studies show that maintaining a positive pressure differential of 0.03 – 0.05 w.g (7.47 psi to 12.4 psi) is the optimal level for inhibiting contaminant infiltration.

• Determining required airflow – Recycling the airflow within the cleanroom helps to reduce contaminant intrusion and removes particles brought in by operators entering the cleanroom. Managing the airflow rate involves analyzing the occupancy rate, the floor traffic, and the number of particles the manufacturing process generates. Manufacturers can use discrete event simulation (DES) models to optimize capacity planning using airflow as a constraint. A DES model can help planners determine the best balance between occupancy rates, floor traffic, and its effect on particle production. The simulation results can then be applied to optimize the cleanroom’s layout and airflow.

Recommendations for medical device manufacturers

Implementing a regulatory-centric approach to manufacturing medical devices increases the commercial opportunities offered by new devices. The approach will ensure that all stages are properly handled and documented — from product development to manufacturing within cleanrooms — to pass inspections and receive global certifications.

Cleanrooms are integral to the governmental regulatory checks for new medical devices. At ACHB, we understand how important it is for manufacturing practices to meet the highest of standards and protect the end-user. Contact an ACHB representative today with your questions on medical device manufacture.