cleanroom or clean room is the situation, usually used as part of assembly, including pharmaceutical or logical research items, and in addition to the application of flight semiconductor manufacture with low levels of natural toxins, for example, small organisms, air, evaporated particles, and decoction. All the more precisely, the cleanroom has a controlled level of tainting indicated by the quantity of particles per cubic meter at a predetermined molecular size. By comparison, the outside air in a typical urban area contains 35,000,000 particles for each cubic meter in the size range of 0.5 m and larger in measurement, related to the ISO 9 cleanroom, while an ISO 1 cleanroom does not allow particles in that size range. and only 12 particles for every 0.3 m cubic meter and smaller.
Video Cleanroom
Histori
The modern cleanroom was created by American physicist Willis Whitfield. As an employee of Sandia National Laboratories, Whitfield created the initial plan for a cleanroom in 1960. Prior to Whitfield's invention, earlier cleanrooms often had problems with unpredictable particles and airflow. Whitfield designed his cleanroom with a constant and highly filtered air flow to clean up the dirt. Within a few years of its discovery in the 1960s, Whitfield's modern little rooms have generated over 50 billion USD in worldwide sales.
Most of Silicon Valley's integrated circuit manufacturing facilities are manufactured by three companies: MicroAire, PureAire, and Key Plastics. This competitor creates a laminar flow unit, glove box, clean room and shower, along with a chemical tank and bench used in the integrated 'Wet' Building integrated circuit. These three companies are pioneers of the use of Teflon for air guns, chemical pumps, scrubbers, water guns, and other devices necessary for the production of integrated circuits. William (Bill) C. McElroy Jr. working as an engineering manager, designing a watch room, QA/QC, and designer for all three companies and his design adds 45 original patents to the technology of the day. McElroy also wrote a four-page article for MicroContamination Journal, a wet-processing training manual, and a wet-processing and cleanroom equipment manual.
Maps Cleanroom
Overview
Cleanrooms can be very large. All manufacturing facilities can be contained in small rooms with factory floors covering thousands of square meters. They are widely used in manufacturing semiconductors, biotechnology, life sciences, and other fields that are very sensitive to environmental pollution. There are also modular cleanrooms.
The air entering the washroom from the outside is filtered to remove dust, and the air inside is constantly circulated through very high particulate air filter (HEPA) and/or ultra-low particulate water (ULPA) to remove internally generated contaminants.
Staff enter and exit via airlocks (sometimes including air shower stages), and wear protective clothing such as hoods, face masks, gloves, boots, and shirts.
The equipment inside the washroom is designed to produce minimal air contamination. Only mops and special buckets are used. Cleanroom furniture is designed to produce minimal particles and easy to clean.
Common materials such as paper, pencils, and fabrics made from natural fibers are often excluded, and alternatives are used. Cleanrooms are not sterile (ie, free of uncontrolled microbes); only controlled air particles. Particle levels are typically tested using particulate counters and microorganisms that are detected and calculated through environmental monitoring methods.
Some cleanrooms are kept at positive pressure so that if there is a leak, air leaks out of the room instead of unfiltered air entering.
Some HVAC cleanroom systems control humidity to low levels, so additional equipment ("ionizers") is required to prevent electrostatic discharge problems.
Low-level cleanrooms may only require special shoes, with really smooth soles that do not wear off in dust or dirt. However, for safety reasons, shoe soles should not make the danger of slipping. Access to the restroom is usually limited to those who wear a clean room suit.
In rest rooms where air contamination standards are less tight, the entrance to the restroom may not have an air shower. The porch (known as the "gray room") is used to wear clean room clothes.
Some manufacturing facilities do not use clean rooms that are fully classified, but use some cleanroom practices to maintain their contamination requirements.
Airflow principle
Cleanrooms maintain free air particles through the use of HEPA or ULPA filters using the principle of laminar or turbulent airflow. Laminar, or unidirectional, air flow system directs air filtered downward or horizontally in a constant stream to a filter located on the wall near the toilet floor or through an elevated hollow panel panel for recirculation. Laminar airflow system is typically used in 80% of the ceiling to keep the air processing constant. Stainless steel or other non-shedding materials are used to build filter and laminar filter air filters to prevent excess particles from entering the air. The turbulent, non-unidirectional airflow, using both laminar air flow hoods and nonspecific filter speeds to keep air in the cleanroom in constant motion, though not all in the same direction. The rough air tried to catch the particles that might be in the air and pushed them to the floor, where they entered the filter and left the clean room environment. The US and EU FDA has set guidelines and limits strict microbial pollution to ensure freedom from microbial contamination in pharmaceutical products.
Contamination of cleanrooms personnel
In the health and pharmaceutical care sector, control of important microorganisms, especially microorganisms that are likely to be deposited into the airflow from shedding of the skin. Studying the microflora cleanroom is essential for microbiologists and quality control personnel to assess trend changes. Shifts in this type of microflora may indicate deviations from "norms" such as resistant strains or problems with cleaning practices.
In assessing the cleanroom microorganisms, the typical flora is mainly related to human skin (Gram-positive cocci), although microorganisms from other sources such as the environment (Gram-positive rods) and water (Gram-negative rods) are also detected, although in larger quantities low. Common bacterial genera include Micrococcus , Staphylococcus , Corynebacterium , and Bacillus , and the fungal genera include Aspergillus and Pencils .
Cleanroom classification and standardization
Cleanrooms are classified according to the number and size of permitted particles per air volume. Large numbers like "class 100" or "class 1000" refer to FED-STD-209E, and indicate the number of particles of 0.5 Âμm or larger size allowed per cubic foot of air. This standard also allows interpolation; for example SNOLAB is maintained as a 2000 classroom cleanroom.
A separate air particle counter, light scattering is used to determine the concentration of air particles, equal to and greater than the specified size, at the specified sampling location.
A small number refers to the ISO 14644-1 standard, which sets the decimal logarithm of 0.1 Âμm or larger particle count allowed per m 3 air. So, for example, a 5th grade ISO cleanroom has at most 10 5 particles/m 3 .
Both FS 209E and ISO 14644-1 consider log-log relationships between particle size and particle concentration. For that reason, the concentration of zero particles is absent. Some classes do not require testing of some particle size, because the concentration is too low or too high to be practical to test, but such blanks should not be read zero.
Since 1 m 3 is about 35Ã, ft 3 , the two standards are mostly equivalent when measuring 0.5 μm particles, although the test standards are different. The air of a regular room is about 1.000.000 class or ISO 9.
ISO 14644-1 and ISO 14698
ISO 14644-1 and ISO 14698 are non-governmental standards developed by the International Organization for Standardization (ISO). The first applies to clean rooms in general (see table below); the latter to cleanrooms where biocontamination might be a problem.
US FED STD 209E
US FED-STD-209E is the federal standard of the United States. It was officially canceled by the Public Service Administration on November 29, 2001, but is still widely used.
EU GMP Classification
The EU GMP guidelines are tighter than others, requiring cleanrooms to meet the number of particles during operation (during manufacturing) and during breaks (when the manufacturing process is not done, but the AHU rooms are on).
BS 5295
BS 5295 is the English Standard.
BS 5295 Class 1 also requires that the largest particle present in any sample should not exceed 5 m. BS 5295 has been replaced, withdrawn since 2007 and replaced with "BS EN ISO 14644-6: 2007".
See also
- Air Quality Index
- Data recovery lab
- Safe environment
- Contamination control
- Pneumatic filter
- Air ionizer
- semiconductor device fabrication
- The particle counter
References
External links
- Cleanroom Wiki - The Global Community for Contamination Control (GSFCC)
- Net Space Requirements in Pharma
- Secretariat for ISO/TC 209 Clean Room and associated controlled environment, group of experts negotiating all aspects of 14644 standard
Source of the article : Wikipedia
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