ISO Class 5 Cleanroom: Class 100 Cleanroom Requirements

Depending on the manufacturer’s choice, clean rooms are regulated by government agencies, International Organization for Standardization, or industry standards, and they have to meet ISO 14644, GMP and FDA standards.

Cleanrooms Classification, Standards, and Requirements

Cleanrooms must comply with ISO 14644, FDA, and GMP standards. They are classified from ISO 9 to ISO 1 class.

In semiconductor production, biotechnology, and other highly sensitive areas where environmental contamination is a problem, cleanrooms can span thousands square meters.

Here is the graph that shows all ISO 14644-1 cleanroom standards and classifications, as well as FED STD 209 equivalent:

What is ISO Class 5 Cleanroom? – Its Classification and Standards

Cleanrooms classified as ISO 5 are extremely clean. The cleanroom must have less than 3,520 particles larger than 0.5 microns per cubic meter and 250-300 HEPA filtered air changes per hour. In other words, the equivalent FED class is 100 particles per cubic foot.

ULPA filtration is 99.9995% effective at 0.12 microns. Common purposes are semiconductor manufacturing and pharmaceutical packing areas.

The following industries frequently use ISO class 5 cleanrooms:

• Life Sciences (Chemistry and Medical Biology)
• Computer & Electronic Part Manufacturing
• Food Manufacturing Industries
• Aerospace Industry
• Biotech Industry
• Nanotechnology

To reach ISO Class 5 air cleanliness in a classified room, one must pass through an ISO 8 (anteroom), an ISO 7, and then an ISO 6 before entering the ISO class 5 cleanroom.

However, you can reach ISO 5 cleanrooms with two or three airlocks. When designing a cleanroom layout, many factors must be considered. For example, the number of people working inside, how much heat the room will generate, and the size of the room.

Moreover, ISO 5 or class 100 cleanrooms need unidirectional airflow. Compared to non-directional airflow cleanrooms, unidirectional airflow cleanrooms use much more air. The whole ceiling is covered in high-efficiency filters.

Filtered air sweeps down the room in a unidirectional manner, at a velocity between 0.3 m/s and 0.5 m/s, with GMP A/B (EU GMP grade standard) also looking at 5.0µ before exiting through the floor, removing all airborne contamination. Cleaning areas that use unidirectional airflow are more expensive compared to directional counterparts. Still, they can comply with rigorous classifications such as ISO 5 or lower.

To achieve ISO Class 5, monobloc and hardwall cleanroom construction is the best option. For example, monobloc is an ideal solution for companies striving for GMP standards and regulations. It accommodates features such as coved floors and interlocked doors.

Design Requirements for ISO Class 5 Cleanroom

Mandatory ISO 5 Cleanroom Testing

As with other cleanroom classes, ISO 5 cleanrooms must undergo the same testing procedure. Cleanrooms are typically tested and certified after construction is complete to ensure they are built according to specifications.

Testing comprises of airflow test, air pressure cascade and particle count test. It is done according to ISO 14644-1, ISO 14644-2, and ISO 14644-3. These tests can also monitor relative humidity, temperature, lighting, noise, and vibration if needed.

• Airflow: maximum time 6 months, test method ISO 14644-1 Annex B4
• Air Pressure Cascade: maximum time 6 months, test method ISO 14644-1 Annex B5
• Particle Count Test: maximum time 6 months, test method ISO 14644-1 Annex A

How to Control Particle Levels in a Cleanroom?

A cleanroom’s cleanliness is affected by the following factors:

• The design and layout of cleanrooms should incorporate gray zones, associated systems, an air preparation system, and accessories specific to cleanrooms and required by the technology.
• HVAC systems require a calculated number of filter changes, including HEPA and ULPA filters.
• Variable pressure prevents contaminated air from entering a cleanroom (over- and under-pressure).
• Made of easy-to-clean materials that do not produce particles, dirt, or chemicals.
• The staff MUST wear protective clothing when entering the cleanroom.
• Keeping the air in a cleanroom as clean as possible is essential.
• The room should be cleaned with

How to Control the Contaminant Levels in an ISO 5 Cleanroom?

It can be challenging to keep the contaminant level low in a cleanroom, but here’s what everyone can do to control it:

• Don’t go straight into the cleanroom after smoking
• Wash clothes before entering and after leaving
• Wash hands before and after leaving
• Do not bring needless equipment
• Cover hair/beard with a hairnet
• Move slowly and calmly
• Talk as little as possible

Cleaning ISO Class 5 Cleanrooms

Cleanliness is achieved through a higher level of filtration. Cleaning should be done daily or weekly, depending on the job’s demands. Take a look at the cleaning process here: