28th May 2025

Cleanrooms are vital for medical device manufacturing because they provide a controlled environment which effectively minimises the risk of contamination. This ensures both the safety and reliability of medical devices for healthcare settings. Different cleanroom classifications are based on the number of particles allowed per cubic metre of air.

Maximum concentration limits (particles/m³of air for

particles equal to and larger than the sizes listed below)

Class	FED STD 209E Equivalent	0.1 micron	0.2 micron	0.3 micron	0.5 micron	1 micron	5 micron
ISO 1		10	2
ISO 2		100	24	10	4
ISO 3	1	1,000	237	102	35	8
ISO 4	10	10,000	2,370	1,020	352	83
ISO 5	100	100,000	23,700	10,200	3,520	832	29
ISO 6	1,000	1,000,000	237,000	102,000	35,200	8,320	293
ISO 7	10,000				352,000	83,200	2,930
ISO 8	100,000				3,520,000	832,000	29,300
ISO 9						8,320,000	293,000

The European standard for cleanroom classification is referred to as “Classification of Air Cleanliness” or BS EN ISO 14644-1:2015. At BDK, we operate three class 7 (class 10,000) cleanrooms which are bio-burden controlled to ensure compliance with BS EN ISO 14644. We have recently increased our environmental control and monitoring level to align with GMP category 3 protocols. In this article, we’ll explore the key parameters that are monitored for cleanrooms further.

Key Cleanroom Parameters

Particulate Levels

The ISO 7 specification for cleanrooms permits up to 352,000 particles per cubic metre for particles 0.5 microns or larger. The ISO 8 specification permits up to 3,520,000 particles per cubic metre for particles 0.5 microns or larger. This can be measured with particle counters and the frequency of monitoring will differ depending on the ISO specification. Particulate and contamination levels are important to ensure full sterilisation can be achieved and to keep the sterilisation dose low, so there are no adverse effects on materials and their performance.

Temperature & Humidity

Temperature and humidity are both controlled as they can have an effect on the following parameters:

Adhesive Bonding: Both temperature and humidity significantly affect curing and adhesion quality.
Static Control: Low humidity increases static discharge risk, which can damage sensitive electronics.
Microbial Growth: High humidity promotes microbial proliferation, which is critical in sterile environments.
Material Stability: Fluctuations in temperature and humidity can cause expansion, contraction, or degradation of materials.

Temperature will typically remain between 18 and 25 degrees. On the other hand, humidity ranges between 40% and 60%. In some cases, more stringent control may be required in terms of sensitive research and development.

Air Pressure Differentials

Maintaining specific air pressure requirements is also key for preventing contamination. The cleanroom will usually be maintained at a positive pressure which is greater than the surrounding area. This ensures unidirectional air flow from clean to less clean areas keeping contaminants out of the cleanroom, preventing cross-contamination between zones and stopping unfiltered air from entering.

Microbial Contamination

Cleanrooms must maintain strict microbial control to ensure product safety and compliance. The typical practices for monitoring microbial contamination include the use of HEPA filtration, gowning protocols and environmental monitoring programs. This is particularly important for products used for both wound care and diagnostics, where sterility and cleanliness are critical. Settles plats, active air sampling, and contact plates are commonly used methods to detect and quantify microbial contamination in the cleanroom environment.

VOCs

Volatile organic compounds (VOCs) are addressed by monitoring solvent levels in environments where adhesives are cured or processed. This is critical for occupational health, product safety as well as flammability considerations.

Surface Cleanliness

Surface cleanliness is critical with ISO standards ranging from ISO 5 to IOS 8. This ensures a low risk of contamination through the use of adhesion-critical surfaces. This and swab testing are crucial for both cleanliness and bond success.

Cleanroom Monitoring Strategies & Technologies

There are many different strategies and technologies for monitoring key cleanroom variables. This includes both manual and automated systems. In some cases, variables can be continuously monitored while it is also important to ensure audit readiness and full traceability of environmental data. As you can see, there are numerous parameters monitored for cleanrooms that are significant for medical device manufacturing. BDK has a clear commitment to quality through strict environmental control and are confident we can support your medical manufacturing requirements. Contact us today to get your project started.

from the Blog What Parameters Are Monitored in Cleanrooms?