ISO 7 Cleanroom Requirements
Cleanrooms are essential for maintaining environmental control in industries where airborne particles can compromise the integrity, safety, or performance of your products. By regulating particulate concentration, temperature, humidity, and airflow, cleanrooms ensure quality and compliance during critical processes.
Among the various cleanroom classifications defined by ISO 14644-1, the ISO 7 cleanroom is one of the most commonly used. It offers a practical balance between contamination control and efficiency that’s ideal for many manufacturing and laboratory environments.
ISO Class 7 Cleanrooms: Key Standards and Requirements
Generally, an ISO Class 7 cleanroom must meet these minimum standards:
Minimum 60 air changes per hour (ACH), providing continuous dilution and removal of airborne contaminants to ensure effective contaminant removal
High-efficiency particulate air (HEPA) filters that remove 99.97% of particles greater than or equal to 0.3 microns
Maintained positive pressure differentials between clean zones and adjacent areas to prevent ingress of contaminants
Regular testing to ensure compliance with ISO 14644-1 standards
One of the most important ISO 7 cleanroom requirements is the maximum allowable concentration threshold.
The limit for particles 0.5 microns and larger is 352,000 per meter squared
The limit for particles 1 micron and larger is 83,200 per meter squared
The limit for particles 5 microns and larger is 2,930 per meter squared
There are no ISO class 7 thresholds for particles 0.1, 0.2, or 0.3 microns in size.
ISO Class 7 Cleanrooms vs. Class 10,000 Cleanrooms
Under Federal Standard 209 E, the Class 10,000 cleanroom required the same level of airborne particles as the Class 7 cleanroom does today. Use of Federal Standard 209 E was discontinued in the year 2001.
Although the term “Class 10,000 cleanroom” is no longer officially in use, you may hear it referenced by long-time industry professionals. If you encounter this term when researching requirements, know that Class 10,000 cleanrooms and ISO Class 7 cleanrooms are essentially the same thing.
When ISO Class 7 Is the Optimal Choice
An ISO 7 cleanroom provides effective contamination control for processes that don’t require the ultra-sterility of ISO 5 or ISO 6. Often combined with ISO Class 5 hoods, this design creates safe transfer zones while supporting reliable, cost-efficient cleanroom operations.
Industries Commonly Using ISO 7 Cleanrooms
ISO 7 cleanrooms are critical to the following sectors:
Pharmaceuticals: Blending, compounding, and packaging non-sterile items
Biotechnology: Quality control labs and analytical testing environments
Electronics: Printed circuit board assembly and sensor manufacturing
Non-Sterile Medical Devices: Production of diagnostic equipment or non-invasive devices
Food and Cosmetics: Filling and sealing of sensitive consumer products
Aerospace and Automotive: Assembly of components that require precision and cleanliness
ISO 7 cleanrooms allow businesses in these industries to carry out their core operations while preserving product quality.
The ISO 5 and ISO 6 Cost-Benefit Balance
Compared to ISO 5 and ISO 6 environments, ISO 7 cleanrooms:
Have lower HVAC and energy demands
Accommodate less intensive gowning and cleaning protocols
Require less frequent and less rigorous maintenance
As such, ISO 7 cleanrooms are an excellent choice for companies needing to meet regulatory requirements without investing in unnecessary infrastructure.
Comparing ISO 7 to ISO 5 and ISO 6
ISO 5 and ISO 6 environments have more rigorous particle allowances. However, maintaining these cleaner environments requires additional equipment and infrastructure. While there are benefits to using a higher ISO class, it’s all about what regulations your organization operates under.
Keep in mind that you don’t have to voluntarily implement a more stringent ISO class. However, you cannot operate in a space that is not clean enough, either.
Design and Operational Considerations for ISO Class 7 Cleanrooms
When designing an ISO 7 cleanroom for your business, you will need to account for these key factors:
Airflow and Filtration
Achieving adequate filtration is one of the most critical aspects of cleanroom design. You need HEPA filters that are strategically placed to deliver adequate coverage. Return air grilles are also vital. Installing them near the floor encourages downward air movement and decreases the risk of contaminating your workspace.
You’ll also want to circulate air through pre-filters and final filters to maintain clean conditions.
Room Layout and Zoning
It’s easy to become hyper-focused on the clean workspace itself. However, you also need to provide gowning areas to reduce contamination from personnel and ensure there are differential pressure areas to prevent backflow. It’s also important to ensure that surfaces are smooth, sealed, and easily cleanable.
Environmental Monitoring
Getting your cleanroom up and running is a huge step in the right direction. However, you’ll need to ensure it remains compliant by regularly performing the following:
Particle counts using handheld or remote-mounted counters
Filter integrity tests
Air velocity and pressure differential measurements
Surface and microbial sampling
If any of the cleanroom’s equipment is not up to standard, you have to take the space out of operation until repairs are made.
Maintenance Practices
To preserve cleanliness, make sure that you:
Regularly inspect and replace filters as scheduled
Clean surfaces with lint-free wipes and approved solvents
Undergo routine training to minimize contamination risk from clothing, skin, or improper movement
Use a checklist or assign a secondary person to verify that these tasks are being completed as scheduled. Even small oversights can compromise your workspace.
Challenges and Mitigation Strategies
Maintaining a high-functioning ISO 7 cleanroom requires discipline and consistency. Here are some challenges you may encounter along the way.
Human Contamination
People make mistakes. Even if they do everything right, operators may shed particles and bring contaminants to the workspace. Make sure your team is trained on proper gowning protocols and has access to critical protective gear.
Compliance Fatigue
Over time, your staff may overlook cleanliness procedures or cut corners. Regular audits and periodic refresher courses can help keep your protocols top of mind. It’s also helpful to ensure you’re not overinvesting in unnecessary controls.
Process-Driven Contaminants
In some industries, the processes themselves generate dust or particles. Identifying these sources and isolating them within enclosures is an effective way of maintaining ISO 7 standards.
Need a Compliant ISO 7 Cleanroom? Contact CleanAir Solutions
An ISO 7 cleanroom offers a good option for use cases that require a moderate level of cleanliness. It provides reliable contamination control without the capital and operating expenses of more restrictive classifications.
If your organization needs an ISO 7 cleanroom, connect with the cleanroom design experts at CleanAir Solutions. We can create an optimal setup for your specific needs. Contact us to get started with a free quote today.