Cleanrooms: Controlled Environments

In a manufacturing environment, complete sterilization is more important than you might think.

A cleanroom is a controlled environment where products are manufactured, typically found in electronics, bio-pharmaceutical, medical device and pharmaceutical industries. Clean-rooms are planned and manufactured using strict protocols. Did you know that a particle 200 times smaller than a human hair could cause a major disaster in a cleanroom?

In order to keep that environment sterilized, contaminants that are developed due to people, processes, equipment or facilities need to be controlled to specific limits. Airborne contamination must be continually removed which impacts factors such as air flow rates, pressurization, temperature, humidity and filtration.

There are four principles which apply to the control of airborne contamination in cleanrooms, but we believe there should be a fifth principle added to that list.

The four recognized principles are:

  • Filtration: Cleanrooms need to be designed so that most of the contamination in the air is filtered out.
  • Dilution: Cleanrooms need to be supplied with a sufficient volume of fresh air at regular intervals so that any contamination generated by people working in the room is first diluted and then removed from the room. This is achieved by having a set number of air changes per hour. The minimum requirement is normally twenty air-changes per hour (that is the room air volume is replaced every three minutes).
  • Directional Air Flow: For ultra-clean activities undertaken in unidirectional airflow cabinets operating at EU and WHO Grade A (ISO class 5), the air needs to move in a straight direction so that any contamination generated within the area is removed. This is achieved by having the air enter at a high velocity (normally at 0.45 meters per second ±20%).
  • Air Movement: The air within a cleanroom needs to keep moving so that any contamination remains suspended in the air rather than being allowed to settle onto surfaces. This is achieved by having unidirectional or turbulent airflow.

The fifth principle we would add to this list would be ionization. Adding ionization to the air coming into the rooms or at various workstations where people and plastics are part of the process…and the problem. Ionization will help to dislodge particles, keep particles airborne and reduce static levels on plastics that will prevent the attraction of contaminants.

Preventing any contaminants from entering a clean-room requires a commitment, but the importance should not be underestimated. Follow strict procedures and guidelines for entering and cleaning clean rooms to ensure that your product is not compromised! Check out some of our products to help keep your cleanroom up to the highest standards.