A contaminate is any foreign substance that will have a detrimental effect or deteriorate whatever that one trying to accomplish. Submicroscopic matter/particle is the most significant form of contamination in Clean Rooms that are distributed in the air in the form of fine particles or fibers or carried into the Clean Room and redeposit by workers.
Most significant source of contamination is the operating personnel
- Hair
- Skin
- Dandruff
- Oral and nasal emissions
This is a partial list of some of the commonly known contaminants that can cause problems in some Clean Room environments. It has been found that many of these contaminants are generated from five basic sources.
Facilities
- Walls, floors and ceilings
- Paint and coatings
- Construction material (sheet rock, saw dust etc.)
- Air conditioning debris
- Room air and vapors
- spills and leaks
People
- Skin flakes and oil
- Cosmetics and perfume
- Spittle
- Clothing debris (lint, fibers etc.)
- Hair
Tool Generated
- Friction and wear particles
- Lubricants and emissions
- Vibrations
- Brooms, mops and dusters
Fluids
- Particulates floating in air
- Bacteria, organics and moisture
- Floor finishes or coatings
- Cleaning chemicals
- Plasticizers (outgases)
- Deionized water
Product generated
- Silicon chips
- Quartz flakes
- Clean room debris
- Aluminum particles
Contamination control technology
In today’s modern world of manufacturing and research and development, contamination control technology has become necessary part of the manufacturing processes. Contamination control technology is not confined to any one industry. Without contamination control technology, the developing broad field of life sciences encompassing biotech, biomedical, pharmaceutical and drug, microelectronic and aerospace would not have been able to achieve the success and new discoveries.
The primary focus of a Clean Room is to control the levels of contamination by creating a differential pressure between the Clean Room and the surrounding area and to filter the air entering the room to prevent the entry of unwanted particulate matter and to change the air in the room with an air-handling system to purge particulate matter created within the room.
Air showers are self contained chambers installed at entrances to clean rooms and other controlled environments. They minimize particulate matter entering or exiting the clean space. Personnel and material entering the exiting the controlled environment are scrubbed by high velocity HEPA – filtered air jets with velocities of 20-22m/s (4000-4300 fpm).
Contaminated air is then drawn through the base within the unit, filtered and recirculated. Air showers can solve many decontamination problems by offering an effective way of reducing the contaminants carried by individual entering or leaving a controlled area.
The greatest source of particulate contamination in a clean room is the operator/personnel. Air showers are installed between change areas and the clean room. The Air shower enhances clean rooms operating protocol by serving as a reminder to all operators that they are entering a controlled environment. Personnel therefore develop the habit of growing up properly before entering the Air Shower.
Air Shower does reduce particulate and the reduction in particulate matter is dependent upon the particle size, the type of garment worn, the cycle time, and the directly relates to the Air Shower design and how it is used and maintained.
Pass box is used for transferring the materials from and into the Clean Room or the uncontrolled environment to the controlled environment. Controlling the ingress of particulate contamination into Clean Rooms and other controlled environments is paramount in order to maintain the integrity of products and processes.
Personnel traffic is the most important factor which should be controlled. Pass Box allows materials to be transferred into the controlled environment without actual personnel movement. Pass Box may also be used to protect the external environment from egress (the act of coming and going our) of contamination, for example, in biological safety laboratory applications.
