Considerations for Contamination Control Strategy 

What Factors Does the CCS Consider?

A CCS isn’t just a document sitting on a shelf. It’s a living plan that asks: What could go wrong in this environment, and how do we stop it? To answer that, it considers several critical factors.

1. The Activity in Each Area

Not all areas of a cleanroom are used for the same purpose. For example:

• A lower-grade area might be used for washing containers.
• A higher-grade area might be used for sterile filling.

Each activity carries its own level of risk, so the CCS must clearly define what is and isn’t permitted in each grade of cleanroom.

2. Movement of People

People are the biggest source of contamination in cleanrooms. The CCS looks at:

• How do people move between areas of different grades?
• How much movement is happening inside the cleanroom itself?

3. Number of People in the Cleanroom

Each person generates particles, no matter how carefully they are gowned. If one person produces X particles, three people will naturally produce 3X. Add movement, and the number multiplies even more.

That’s why the CCS must control not only who enters the cleanroom, but also how many people are inside at once.

4. Equipment in the Cleanroom

Every time equipment or materials are transferred in or out, there is a risk of contamination. The CCS must ask:

• Is this equipment really needed inside?
• How will it be cleaned before entry?
• How will it be handled while inside?

If a risk can’t be eliminated, the CCS ensures that appropriate controls are in place, such as dedicated cleaning, transfer procedures, or restricted use.

5. Cleanliness of the Air

Air is the invisible lifeline of the cleanroom. It passes through high-efficiency filters (HEPA or ULPA) before it ever reaches the working area. The CCS must ensure that:

• Cleanrooms and change rooms meet the correct cleanliness standard.
• Air filters are suitable for the level of protection required.
• Monitoring systems are in place to constantly check air quality and pressure differences.

If the air is not clean, the product is not safe — it’s that simple.

6. Use of Isolators or RABS

Finally, the CCS considers whether additional technology, such as isolators or RABS (Restricted Access Barrier Systems), should be used. These systems add another layer of protection by creating a barrier between the operator and the product, further reducing contamination risk.