What is a Cleanroom and how? – Part II

April 17th, 2009
By John Krause

In an earlier blog; “What is a Cleanroom any how?” I promised to address more on what is contamination. What are some sources of contamination? Here is a partial list of some possible sources of contamination;

The Facility
Walls, floors and ceiling
Coatings and Paint
Constructions debris, i.e., (sheet rock dust )
Vapors
Spills & leaks

People

Skin flakes
Cosmetics
Spittle
Clothing (lint, fibers )
Hair

Generated Particulates

Friction and wear particles
Lubricants and emissions
Vibrations
Brooms, mops and v dusters

Fluids

Particulates floating in air (aerosol )
Bacteria and other organics
Floor finishes or coatings

Cleaning chemicals

Plasticizers (out gassing )
Deionized water

Product generated

Silicon chips
Quartz flakes

PEOPLE IN CLEANROOM:

There are both physical and psychological concerns when humans are present in cleanrooms .
Physical behavior such as fast motion and horseplay can increase contamination dramatically.
Psychological concerns like room temperature, humidity, claustrophobia , odors and workplace attitude are important.

Several ways people produce contamination:

Body Regenerative: Skin flakes, oils, perspiration and hair.
Behavior. Rate of movement, sneezing and coughing.
Attitude: Work habits and communication between workers.
The fact is that a major source of contamination in the cleanroom is the personnel, the people who work in it.

Look at the activities listed below and notice the number of particles produced per minute during these activities.

PEOPLE ACTIVITY PARTICLES/MINUTE (0.3 microns and larger )
Motionless (Standing or Seated) 100,000
Walking about 2 mph 5,000,000
Walking about 3.5 mph 7,000,000
Walking about 5 mph 10,000,000
Horseplay 100,000,000

While these are just some basics, I hope it helps some friends, neighbors and some of he people that have had little, or recent experience with cleanrooms and what goes on inside them. Did you know any of this stuff? What did I miss that you think people new to the industry or considering taking a new job in a cleanroom should know? Post your reply at http://www.johnkrause.me/