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Clean Room Classifications & ISO Standards

Clean Room Classifications & ISO Standards Jul. 13, 2023

Clean Room Classifications & ISO Standards

Our team can design, manufacture and install your certified cleanroom in as little as 4 weeks , on-site with minimum disruption.

A Turnkey Complete Cleanroom is when the modular cleanroom company provides beginning to end service, doing all aspects of the cleanroom project. This includes:

A Mask Manufacturing Cleanroom is a cleanroom that is used for manufacturing of K95 and surgical masks during the Covid-19 crisis.

A Static Dissipative Cleanroom is designed to prevent static from building up within the cleanroom which can damage sensitive electronic components. Features include:

FAQs About Cleanroom Classifications

Q: What Is a Cleanroom?

A: A cleanroom (or clean room) is a room that has HEPA filtration to remove particles from the air. Cleanrooms are used for manufacturing where high levels of cleanliness and sterility are required. Common applications are medical devices, pharmaceutical and semiconductor manufacturing. The FDA mandates the use of cleanrooms to create GMP manufacturing factories.

Q: What Are Cleanrooms Used For?

A: Cleanrooms are used for manufacturing where high levels of cleanliness and sterility are required. Common applications are medical devices, pharmaceutical and semiconductor manufacturing. Cleanrooms use HEPA filters to remove particles from the air. It is common to see pharmaceutical cleanrooms, medical device cleanrooms, semiconductor cleanrooms, electronic cleanrooms, aerospace cleanrooms, food cleanrooms, USP797 compounding pharmacy cleanrooms and biotech cleanrooms. Cleanrooms are also used by the government such as national labs, defense industries, and R&D labs at universities.

Q: How Clean Is a Cleanroom?

A: Very clean. A class 100 cleanroom has 100 particles per cubic foot. By comparison your typical office space has between 500,000 and 1 million particles per cubic foot. Cleanrooms come in different classes from class 100 to 100,000.

Q: When Is a Cleanroom Required?

A: Medical device and pharmaceutical manufacturing requires sterile environments to produce their products. Cleanrooms provide this sterile super clean manufacturing space which reduces the chance of contamination getting in your medicine. Semiconductor manufacturers produce devices with ultra small super dense features. Examples are computer chips for your cell phone or PC. If contamination were to get on the chip during manufacturing, they would not work.

Q: What Does ISO Stand For?

A: ISO is the International Standards Organization. It has created the ISO 4644-1 Cleanroom Standards that describe the allowed number of particles, the allowed size of particles and HEPA filtered air flow changes per hour meet ISO-4, ISO-5, ISO-6, ISO-7, and ISO-8 standard. It relies on measurements per cubic meter. It corresponds to the USA based Fed Standard 209E which relies on measurements per cubic foot. Fed Standard 209E corresponding classes are 10, 100, 1000, 10k and 100k.

Q: What is Clean Room in Pharma?

A: In pharma a clean room is a controlled environment using HEPA filtration to minimize particulate contamination. Pharmaceutical manufacturers are subject to FDA validation of their manufacturing which typically specify use of a clean room to ensure the quality of the manufactured pharmaceutical product. Sterility is highest priority. Pharma cleanrooms focus on both non viable (inanimate) and viable (live) contamination. They typically use laser particle counters to measure non viable contamination levels and settling plates with culture media to measure viable contamination levels. Pharmaceutical cleanrooms use aggressive chemical and UV light cleaning techniques to maintain sterility.

Q: What is a Data Cleanroom?

A: A data cleanroom is a secure isolation virtual platform that typically stores anonymized marketing data from multiple sources. It is used to protect privacy and share data from multiple sources. It is very different from physical cleanrooms used for manufacturing.

Q: How Do Cleanrooms Work?

A: Cleanrooms rely on HEPA or ULPA filtration to remove particles from the air and create an ultra clean environment. With sufficient air changes per hour and laminar air flow it is possible to reduce particulate count from greater then 500k/ft3in typical office space to as low as 100/ft3(class 100 cleanroom). Airlocks are used to prevent contamination from entering the cleanroom. Workers inside cleanrooms typically wear cleanroom garments such as booties and bunny suits to prevent them from bringing contamination into the room. Eating and drinking are never allowed in cleanrooms.

Q: Who Needs a Cleanroom?

A: Industries such as pharmaceutical, medical device and USP797 compounding pharmacies are required by the government to manufacture in sterile environment and must use cleanrooms. Other industries such as semiconductor, electronics, aerospace and optics find the ultra-clean environments in cleanrooms are the only way to cost effectively manufacture their products. Other industries that use cleanrooms include food, beverage, e-liquid, CBD and vitamins.

Q: What is a Pharmaceutical Cleanroom?

A: Pharmaceutical manufacturers are subject to FDA validation of their manufacturing which typically specify use of a clean room to ensure the quality of the manufactured pharmaceutical product. Sterility is highest priority. Pharmaceutical cleanrooms focus on both non viable (inanimate) and viable (live) contamination. They typically use laser particle counters to measure non viable contamination levels and settling plates with culture media to measure viable contamination levels. Pharmaceutical cleanrooms use aggressive chemical and UV light cleaning techniques to maintain sterility.

Q: What is a Class 1 Cleanroom?

A: A class 1 cleanroom refers to ISO standard allowing less than 2 particles greater than 0.3 microns and no particles greater than 1.0 microns per cubic meter. A class 1 cleanroom typically has from 500-750 air changes per hour and typically utilizes ULPA filtration. Other common characteristics are 100% ULPA ceiling coverage and raised floors. It is the cleanest classification.

Q: What is a Class 2 Cleanroom?

A: A class 2 cleanroom refers to ISO standard allowing less than 11 particles greater than 0.3 microns and no particles greater than 1.0 microns per cubic meter. A class 2 cleanroom typically has 500-750 air changes per hour and typically utilizes ULPA filtration. Other common characteristics are 100% ULPA ceiling coverage and raised floors. It is the 2nd most clean classification.

Q: How Many Types of Cleanrooms Are There?

A: The most common type cleanrooms are modular cleanrooms, stick-built cleanrooms (or standard), and softwall cleanrooms. Modular cleanrooms utilize prefabricated modular wall systems which allow for faster installation, easy modification(s) and reasonable cost. Stick built or standard cleanrooms rely on conventional steel stud(s) drywall construction. It can be slightly cheaper. Softwall cleanrooms use clear vinyl curtains suspended from metal frames. Small softwall cleanrooms are often mounted on casters so they can be easily moved around.

Q: What is a Class 4 Cleanroom?

A: A class 4 cleanroom refers to ISO standard allowing less than 1020 particles greater than 0.3 microns and less than 2 particles greater than 5.0 microns per cubic meter. A class 5 cleanroom requires from 500-600 air changes per hour and typically utilizes ULPA filtration. Other common characteristics are 100% ULPA ceiling coverage and raised floors. It is the 4th most clean classification.

Q: How Do You Prepare For Cleanroom / Installations?

A: If you need an ISO-7 cleanroom you should prepare your facility for the modular cleanroom installation. Check that area is free and clear up to height of cleanroom. Frequently existing electrical conduit, lighting, sprinklers, and HVAC ducting need to be relocated. When installing new cleanroom flooring make sure the existing concrete is in good shape. Have any cracks and depressions filled to level the floor.

Cleanroom Components

BMC offers a full line of Fan Filter Units that provide high efficiency air filtration with low energy consumption, low heat generation and low sound levels. FFU’s are available with HEPA or ULPA filters, and 120v & 277v units are standard, but we can build them to meet practically any electrical requirement. Features include energy consumption of 190 watts, low sound level of 53dba @ 90 FPM face velocity (as tested in an acoustical laboratory).

Minimum filter efficiency is 99.99% at 0.3 microns (HEPA), and maximum filter efficiency is 99.99995% at .12 microns (ULPA). Option available for Fan Filter control controls and monitoring ideal for any cleanroom environments. Option also available for Room Side Replaceable filters allowing replacement of the filter without removing the fan unit from the ceiling grid.

Cleanroom

Dust-free room for research or production

Cleanroom used for the production of microsystems. The yellow (red-green) lighting is necessary for photolithography, to prevent unwanted exposure of photoresist to light of shorter wavelengths. Cleanroom from outside Entrance to a cleanroom with no air shower Cleanroom for microelectronics manufacturing with fan filter units installed in the ceiling grid Cleanroom cabin for precision measuring tools Typical cleanroom head garment

A cleanroom or clean room is an engineered space, which maintains a very low concentration of airborne particulates. It is well isolated, well-controlled from contamination, and actively cleansed. Such rooms are commonly needed for scientific research, and in industrial production for all nanoscale processes, such as semiconductor manufacturing. A cleanroom is designed to keep everything from dust, to airborne organisms, or vaporised particles, away from it, and so from whatever material is being handled inside it.

A cleanroom can also prevent the escape of materials. This is often the primary aim in hazardous biology and nuclear work, in pharmaceutics and in virology.

Cleanrooms typically come with a cleanliness level quantified by the number of particles per cubic meter at a predetermined molecule measure. The ambient outdoor air in a typical urban area contains 35,000,000 particles for each cubic meter in the size range 0.5 μm and bigger, equivalent to an ISO 9 certified cleanroom. By comparison an ISO 14644-1 level 1 certified cleanroom permits no particles in that size range, and just 12 particles for each cubic meter of 0.3 μm and smaller. Semiconductor facilities often get by with level 7 or 5, while level 1 facilities are exceedingly rare.

 

History

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The modern cleanroom was invented by American physicist Willis Whitfield.[1] As employee of the Sandia National Laboratories, Whitfield created the initial plans for the cleanroom in 1960.[1] Prior to Whitfield's invention, earlier cleanrooms often had problems with particles and unpredictable airflows. Whitfield designed his cleanroom with a constant, highly filtered air flow to flush out impurities.[1] Within a few years of its invention in the 1960s, Whitfield's modern cleanroom had generated more than US$50 billion in sales worldwide (approximately $464 billion today).[2][3]

The majority of the integrated circuit manufacturing facilities in Silicon Valley were made by three companies: MicroAire, PureAire, and Key Plastics. These competitors made laminar flow units, glove boxes, clean rooms and air showers, along with the chemical tanks and benches used in the 'Wet Process' building of integrated circuits. These three companies were the pioneers of the use of Teflon for airguns, chemical pumps, scrubbers, water guns, and other devices needed for the production of integrated circuits. William (Bill) C. McElroy Jr. worked as engineering manager, drafting room supervisor, QA/QC, and designer for all three companies and his designs added 45 original patents to the technology of the time. McElroy also wrote a four-page article for MicroContamination Journal, wet processing training manuals, and equipment manuals for wet processing and clean rooms.[4]

 

Overview

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A clean room is a necessity in semiconductor manufacturing, rechargeable battery industry, the life sciences, and any other field that is highly sensitive to environmental contamination.

Cleanrooms can range from the very small to the very large. On the one hand, a single user laboratory can be built to cleanroom standards within several square meters, and on the other entire manufacturing facilities can be contained within a cleanroom with factory floors covering thousands of square meters. Between the large and the small, there are also modular cleanrooms.[5] They have been argued to lower costs of scaling the technology, and to be less susceptible to catastrophic failure.

With such a wide area of application, not every cleanroom is the same. For example, the rooms utilized in semiconductor manufacturing need not be sterile (i.e., free of uncontrolled microbes);[6], while the ones used in biotechnology usually must be. Vice versa, operating rooms need not be absolutely pure of nanoscale inorganic salts, such as rust, while nanotechnology absolutely requires it. What then is common to all cleanrooms is strict control of airborne particulates, possibly with secondary decontamination of air, surfaces, workers entering the room, implements, chemicals, and machinery.

Sometimes particulates exiting the compartment are also of concern, such as in research into dangerous viruses, or where radioactive materials are being handled.

 

Basic construction

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First, outside air entering a cleanroom is filtered and cooled by several outdoor air handlers using progressively finer filters to exclude dust.

Within, air is constantly recirculated through fan units containing high-efficiency particulate absorbing filters (HEPA), and/or ultra-low particulate air (ULPA) filters to remove internally generated contaminants. Special lighting fixtures, walls, equipment and other materials are used to minimize the generation of airborne particles. Plastic sheets can be used to restrict air turbulence, if the cleanroom design is of the laminar airflow type.[7][8][9]

Air temperature and humidity levels inside a cleanroom are tightly controlled, because they affect the efficiency and means of air filtration. If a particular room requires low enough humidity to make static electricity a concern, it too will be controlled by e.g. introducing controlled amounts of charged ions into the air, using a corona discharge. Static discharge is of particular concern in the electronics industry, where it can instantly destroy components and circuitry.

Equipment inside any cleanroom is designed to generate minimal air contamination. The selection of material for the construction of a cleanroom should not generate any particulates, hence monolithic epoxy or polyurethane floor coating is preferred. Buffed stainless steel or powder-coated mild steel sandwich partition panels and ceiling panel are used, instead of iron alloys prone to rusting and then flaking. Corners like the wall to wall, wall to floor, wall to ceiling are avoided by providing coved surface and all joints need to be sealed with epoxy sealant to avoid any deposition or generation of particles at the joints, by vibration and friction.

 

Air flow principles

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Air flow pattern for "Turbulent Cleanroom"

Air flow pattern for " Laminar Flow Cleanroom"

Cleanrooms maintain particulate-free air through the use of either HEPA or ULPA filters employing laminar or turbulent air flow principles. Laminar, or unidirectional, air flow systems direct filtered air downward or in horizontal direction in a constant stream towards filters located on walls near the cleanroom floor or through raised perforated floor panels to be recirculated. Laminar air flow systems are typically employed across 80% of a cleanroom ceiling to maintain constant air processing. Stainless steel or other non shedding materials are used to construct laminar air flow filters and hoods to prevent excess particles entering the air. Turbulent, or non unidirectional, air flow uses both laminar air flow hoods and nonspecific velocity filters to keep air in a cleanroom in constant motion, although not all in the same direction. The rough air seeks to trap particles that may be in the air and drive them towards the floor, where they enter filters and leave the cleanroom environment. US FDA and EU have laid down guidelines and limit for microbial contamination which is very stringent to ensure freedom from microbial contamination in pharmaceutical products.[10] Plenums between air handlers and fan filter units along with sticky mats may also be used.

In addition to air filters, clean rooms can also use ultraviolet light to disinfect the air.[11] UV devices can be fitted into ceiling light fixtures and irradiate air, killing potentially infectious particulates, including 99.99 percent of airborne microbial and fungal contaminants.[12] UV light has previously been used to clean surface contaminants in sterile environments such as hospital operating rooms. Their use in other clean rooms may increase as equipment becomes more affordable. Potential advantages of UV-based decontamination includes a reduced reliance on chemical disinfectants and the extension of HVAC filter life.

 

Cleanrooms of different kinds

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Some cleanrooms are kept at a positive pressure so if any leaks occur, air leaks out of the chamber instead of unfiltered air coming in. This is most typically the case in semiconductor manufacturing, where even minute amounts of particulates leaking in could contaminate the whole process, while anything leaking out would not be harmful to the surrounding community. The opposite is done e.g. in the case of high level bio-laboratories that handle dangerous bacteria or viruses; those are always held at negative pressure, with the exhaust being passed through high efficiency filters, and further sterilizing procedures. Both are still cleanrooms, because the particulate level inside is maintained within very low limits.

Some cleanroom HVAC systems control the humidity to such low levels that extra equipment like air ionizers are required to prevent electrostatic discharge problems. This is a particular concern within the semiconductor business, because static discharge can easily damage modern circuit designs. On the other hand, active ions in the air can harm exposed components as well. Because of this most workers in high electronics and semiconductor facilities have to wear conductive boots while working. Low-level cleanrooms may only require special shoes, with completely smooth soles that do not track in dust or dirt. However, for safety reasons, shoe soles must not create slipping hazards. Access to a cleanroom is usually restricted to those wearing a cleanroom suit, including the necessary machinery.

In cleanrooms in which the standards of air contamination are less rigorous, the entrance to the cleanroom may not have an air shower. An anteroom (known as a "gray room") is used to put on clean-room clothing. This practice is common e.g. in many nuclear power plants, which operate as low-grade inverse pressure cleanrooms, as a whole.

Recirculating vs. One pass cleanrooms

Recirculating cleanrooms return air to the negative pressure plenum via low wall air returns. The air then is pulled by HEPA fan filter units back into the cleanroom. The air is constantly recirculating and by continuously passing through HEPA filtration removing particles from the air each time. Another advantage of this design is that air conditioning can be incorporated.

One pass cleanrooms draw air from outside the cleanroom, pass it through HEPA fan filter units into the cleanroom. The air then leaves through exhaust grills to outside the cleanroom. The advantage of this approach is the lower cost. The disadvantages are comparatively shorter HEPA fan filter life, worse particle counts than a recirculating cleanroom, and that it cannot accommodate air conditioning.

 

Operating procedure

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In order to minimize the carrying of particulate by a person moving into the cleanroom, staff enter and leave through airlocks (sometimes including an air shower stage), and wear protective clothing such as hoods, face masks, gloves, boots, and coveralls.

Common materials such as paper, pencils, and fabrics made from natural fibers are often excluded, because they shed particulates in use.

Particle levels are usually tested using a particle counter and microorganisms detected and counted through environmental monitoring methods.[13][14] Polymer tools used in cleanrooms must be carefully determined to be chemically compatible with cleanroom processing fluids [15] as well as ensured to generate a low level of particle generation.[16]

When cleaning, only special mops and buckets are used. Cleaning chemicals used tend to involve sticky elements to trap dust, and may need a second step with light molecular weight solvents to clear. Cleanroom furniture is designed to produce a minimum of particles and is easy to clean.

A cleanroom is as much a process and a meticulous culture to maintain, as it is a space as such.

 

Personnel contamination of cleanrooms

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The greatest threat to cleanroom contamination comes from the users themselves.[17] In the healthcare and pharmaceutical sectors, control of microorganisms is important, especially microorganisms likely to be deposited into the air stream from skin shedding. Studying cleanroom microflora is of importance for microbiologists and quality control personnel to assess changes in trends. Shifts in the types of microflora may indicate deviations from the "norm" such as resistant strains or problems with cleaning practices.

In assessing cleanroom micro-organisms, the typical flora are primarily those associated with 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 lower number. Common bacterial genera include Micrococcus, Staphylococcus, Corynebacterium, and Bacillus, and fungal genera include Aspergillus and Penicillium.[14]

 

Cleanroom classification and standardization

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The cleanroom processing bay of the KSC Space Station Processing Facility. NASA maintains a standard of 100,000 class in the SSPF[18]

Cleanrooms are classified according to the number and size of particles permitted per volume of air. Large numbers like "class 100" or "class 1000" refer to FED-STD-209E, and denote the number of particles of size 0.5 μm or larger permitted per cubic foot of air. The standard also allows interpolation; for example SNOLAB is maintained as a class 2000 cleanroom.

A discrete, light-scattering airborne particle counter is used to determine the concentration of airborne particles, equal to and larger than the specified sizes, at designated sampling locations.

Small numbers refer to ISO 14644-1 standards, which specify the decimal logarithm of the number of particles 0.1 μm or larger permitted per m3 of air. So, for example, an ISO class 5 cleanroom has at most 105 particles/m3.

Both FS 209E and ISO 14644-1 assume log-log relationships between particle size and particle concentration. For that reason, zero particle concentration does not exist. Some classes do not require testing some particle sizes, because the concentration is too low or too high to be practical to test for, but such blanks should not be read as zero.

Because 1 m3 is about 35 ft3, the two standards are mostly equivalent when measuring 0.5 μm particles, although the testing standards differ. Ordinary room air is around class 1,000,000 or ISO 9.[19]

 

ISO 14644-1 and ISO 14698

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ISO 14644-1 and ISO 14698 are non-governmental standards developed by the International Organization for Standardization (ISO).[20] The former applies to clean rooms in general (see table below); the latter to cleanrooms where biocontamination may be an issue. Since the strictest standards have been achieved only for space applications, it is sometimes difficult to know whether they were achieved in vacuum or standard conditions.

ISO 14644-1 defines the maximum concentration of particles per class and per particle size with the following formula[21]

C N = 10 N ( 0.1 D ) 2.08 {\displaystyle {\text{C}}_{\text{N}}=10^{\text{N}}\left({\frac {0.1}{\text{D}}}\right)^{2.08}}

Where C N {\displaystyle {\text{C}}_{\text{N}}} is the maximum concentration of particles in a volume of 1m 3 ^{3} of airborne particles that are equal to, or larger, than the considered particle size which is rounded to the nearest whole number, using no more than three significant figures, N {\text{N}} is the ISO class number, D {\displaystyle {\text{D}}} is the size of the particle in μ \mu m and 0.1 is a constant expressed in μ \mu m. The result for standard particle sizes is expressed in the following table.

Class Maximum particles/m3 a FED STD 209E
equivalent ≥0.1 μm ≥0.2 μm ≥0.3 μm ≥0.5 μm ≥1 μm ≥5 μm ISO 1 10b d d d d e ISO 2 100 24b 10b d d e ISO 3 1,000 237 102 35b d e Class 1 ISO 4 10,000 2,370 1,020 352 83b e Class 10 ISO 5 100,000 23,700 10,200 3,520 832 d,e,f Class 100 ISO 6 1,000,000 237,000 102,000 35,200 8,320 293 Class 1,000 ISO 7 c c c 352,000 83,200 2,930 Class 10,000 ISO 8 c c c 3,520,000 832,000 29,300 Class 100,000 ISO 9 c c c 35,200,000 8,320,000 293,000 Room air a All concentrations in the table are cumulative, e.g. for ISO Class 5, the 10 200 particles shown at 0,3 μm include all particles equal to and greater than this size.

All concentrations in the table are cumulative, e.g. for ISO Class 5, the 10 200 particles shown at 0,3 μm include all particles equal to and greater than this size.

b These concentrations will lead to large air sample volumes for classification. Sequential sampling procedure may be applied; see Annex D.
c Concentration limits are not applicable in this region of the table due to very high particle concentration.
d Sampling and statistical limitations for particles in low concentrations make classification inappropriate.
e Sample collection limitations for both particles in low concentrations and sizes greater than 1 μm make classification at this particle size inappropriate, due to potential particle losses in the sampling system.

f In order to specify this particle size in association with ISO Class 5, the macroparticle descriptor M may be adapted and used in conjunction with at least one other particle size. (See C.7.)

In order to specify this particle size in association with ISO Class 5, the macroparticle descriptor M may be adapted and used in conjunction with at least one other particle size. (See C.7.)

 

US FED STD 209E

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US FED-STD-209E was a United States federal standard. It was officially cancelled by the General Services Administration on November 29, 2001,[22][23] but is still widely used.[24]

Class Maximum particles/ft3 ISO
equivalent ≥0.1 μm ≥0.2 μm ≥0.3 μm ≥0.5 μm ≥5 μm 1 35 7.5 3 1 0.007 ISO 3 10 350 75 30 10 0.07 ISO 4 100 3,500 750 300 100 0.7 ISO 5 1,000 35,000 7,500 3000 1,000 7 ISO 6 10,000 350,000 75,000 30,000 10,000 70 ISO 7 100,000

 

 

3.5

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106

 

750,000 300,000 100,000 830 ISO 8

Current regulating bodies include: ISO, USP 800, US FED STD 209E (previous standard, still used)

Drug Quality and Security Act (DQSA) created in Nov. 2013 in response to drug compounding deaths and serious adverse events.

The Federal Food, Drug, and Cosmetic Act (FD&C Act) created specific guidelines and policies for human compounding.

503A addresses compounding by state or federally licensed facility by licensed personnel (pharmacist/ physicians)

503B pertaining to outsourcing facilities need direct supervision from a licensed pharmacist and do not need to be a licensed pharmacy. Facility is licensed through the Food and Drug Administration (FDA) [25]

 

EU GMP classification

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EU GMP guidelines are more stringent than others, requiring cleanrooms to meet particle counts at operation (during manufacturing process) and at rest (when manufacturing process is not carried out, but room AHU is on).

Class Maximum particles/m3[26] At Rest In Operation 0.5 μm 5 μm 0.5 μm 5 μm Grade A 3,520 20 3,520 20 Grade B 3,520 29 352,000 2,900 Grade C 352,000 2,900 3,520,000 29,000 Grade D 3,520,000 29,000 Not defined Not defined

 

BS 5295

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BS 5295 is a British Standard.

Class Maximum particles/m3 ≥0.5 μm ≥1 μm ≥5 μm ≥10 μm ≥25 μm Class 1 3,000   0 0 0 Class 2 300,000   2,000 30   Class 3   1,000,000 20,000 4,000 300 Class 4     200,000 40,000 4,000

BS 5295 Class 1 also requires that the greatest particle present in any sample can not exceed 5 μm.[27] BS 5295 has been superseded, withdrawn since the year 2007 and replaced with "BS EN ISO 14644-6:2007".[28]

 

 

USP <800> Standards

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USP 800 is a United States standard developed by the United States Pharmacopeial Convention (USP) with an effective date of December 1, 2019.[29]

 

Ramifications and further applications

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In hospitals, theatres are similar to cleanrooms for surgical patients' operations with incisions to prevent any infections for the patient.

In another case, severely immunocompromised patients sometimes have to be held in prolonged isolation from their surroundings, for fear of infection. At the extreme, this necessitates a cleanroom environment. The same is the case for patients carrying airborne infectious diseases, only they are handled at negative, not positive pressure.

In exobiology when we seek out contact with other planets, there is a biological hazard both ways: we must not contaminate any sample return missions from other stellar bodies with terrestrial microbes, and we must not contaminate possible other ecosystems existing in other planets. Thus, even by international law, any probes we send to outer space must be sterile, and so to be handled in cleanroom conditions.

Since larger cleanrooms are very sensitive controlled environments, within which multibillion dollar industry can take place, sometimes they are even fitted with numerous seismic base isolation systems to prevent costly equipment malfunction.[30]

 

See also

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References

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  • Jenny-YZ-AL: Jenny-YZ-AL

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