Although the revised ISO cleanroom standards have been in place for quite some time – well over 10 years, in fact – there remains the potential for confusion over terminology and nomenclature. In addition, it’s also important to keep in mind that, as with any specification or measurement, there are limitations with these standards.
As a quick refresher, what exactly are the ISO standards and what do they mean? ISO 14644-1 classification of air cleanliness and ISO 14644-2 deal with particle size and particle count, establishing a cleanroom rating of ISO 1-9 based on those factors. As you know, cleanroom users and engineers will typically refer to a room as an “ISO 4,” “ISO 5,” and so on. While lower numbered ISO specs require the full complement of coveralls, shoe covers, and similar garments, higher numbered rooms like an ISO 9 can be entered in garments like a frock covering everyday clothes.
On to the more important point: what are the limitations of these cleanroom measurements? They require less information about the cleanroom than Federal Standard 209 did, and allow for fewer tester locations for cleanliness. The ISO standards establish 0.1 micron as the standard particle diameter, create three new cleanliness classes, and aren’t as concerned with airflow velocity, room pressure, room temperature, and the distance from the floor or the filter face when taking an air sample for a particle count. This variability can lead to fluctuations in particulate levels and thus, in ISO classifications.
Because of these limitations, it’s important to be aware of at what state testing was done: at rest, as built, or in operation, and to keep all factors in mind. When you work with Liberty for your cleanroom needs, you can be sure you’re dealing with experts who know exactly what makes for the best possible cleanroom. You can trust that we are aware of everything that’s crucial to the process, and know your cleanroom will be the best possible.
Anyone who uses a cleanroom knows that the process doesn’t end there. Items built in a contaminant-controlled environment need to be shipped and kept in a contaminant-controlled environment. Clean film packaging provides the answer to this problem, applying the same standards of cleanliness to the packaging as to the end product. Clean film packaging can either be purchased to meet certain requirements, or, with the proper expertise, existing film can be cleaned within a cleanroom. Standards to be met take into account airborne particles, humidity, and temperature control, among others. With the right procedures, clean film packaging can also be a very sustainable, “green” way of packaging cleanroom products. Read on for more.
As you might have guessed, there’s no standard film that can satisfy all requirements. What are the steps in choosing and using the proper clean film packaging? Liberty Industries can help you:
Material Selection: Strength, thickness, and static properties are characteristics to consider, as are more intricate aspects like gas and vapor barrier, film density, and sloughing (shedding plastic particles). Common materials are UCF-POLY, Nylon 6, and ACLAR.
Proper Handling: It’s important to be aware of the clothing beneath your cleanroom garments, and the limitations of the garments – and of antistatic agents for the film. The safest method is just to keep clean film packaging as far away as possible from your person. When trimming or opening the packaging, stainless steel scissors should be used, pushing through the material (rather than chopping) for the cleanest cut possible.
Testing: Ensure that thorough and proper testing is carried out to be confident that the packaging can keep the internal environment free of forbidden particulate matter.
Stay “Green:” As we mentioned above, clean film packaging can be cleaned and reused several times, provided the right facilities and cleaning equipment are available, such as cleaning fluid, electrostatic eliminators, and final processing machinery. In addition, proper recycling procedures should be followed with the plastics once they are discarded, further ensuring that sustainability protocols and goals are met.
For a full and detailed testing procedure, and more information on clean film packaging, be sure to visit this page.
The garments worn in a cleanroom environment are as important as the cleanroom itself. Liberty Industries is here to answer all of your cleanroom garment questions.
How are cleanroom garments designed?
Important factors when designing these garments are: loose fitting; a minimum of seams; no pockets, belts, pleated or tucked areas; tight fabric weave; strongest possible fabric filaments; fabric that reduces static electricity and remains non-linting; sewing threads of monofilament materials; they must cover as much of the body as possible, particularly the neck.
Are cleanroom garments “green?”
When washable, reuseable garments are chosen, they absolutely are. Nylon garments can be reused many times, even for the most stringent cleanroom environments, provided the requisite cleaning facilities and protocols are used. Choosing wash-friendly, durable, high-quality garments will ensure that your organization meets is sustainability and stewardship goals, even for the most exacting cleanroom requirements.
How are cleanroom garments laundered?
There are industrial laundries that are skilled at the cleaning of these garments. As per industry standards, they are required to remove lint and particles in addition to cleaning the garments, and they must be completely free from contamination. Please note: it is not suitable to use everyday detergents for cleanroom garments. They must be brought to specialty cleanroom garment launderers.
What types of garments should be worn in a cleanroom?
Fabrics made with synthetic fibers are preferable. Nylon is a good choice wherever acid and static are not a major factor, as it is crisp, durable, washable, and stain-resistant. Dacron, a polyester fiber, is a bit softer than nylon and drapes more smoothly. It retains whiteness and shape, and is highly wrinkle-resistant. When a high acid resistance is necessary, Dacron is preferable because it melts rather than flames when exposed to fire. When synthetic materials are needed for a cleanroom, a blend of continuous filament yarns, such as dacron and rayon weave, are a good choice.
Cleanrooms are great at maintaining a contaminant-controlled environment, with expertly engineered filtration systems, humidity and temperature controllers, and construction to ensure a totally contamination free workspace. Filters in the cleanroom can only do so much, though, and the job of keeping a cleanroom clean really starts well before anyone sets foot in it. The main purpose of filtration in a cleanroom is to keep microscopic airborne particles from entering the space – they’re not designed to eliminate the everyday dirt, dust, and other particles that accumulate on people and objects who are entering the cleanroom. That’s where the air shower enters the picture.
Depending on the application required in the cleanroom, the air shower can be an integral part of the cleanroom setup. Basically, it does the heavy lifting of cleaning that everyday particulate matter off of a person who is properly attired for cleanroom entry, or object, prior to entering the cleanroom space. A system of high pressure air nozzles spray clean air at high pressure on the entrant, literally scrubbing the entrant of forbidden contaminants. Filters trap the dirty air and keep it out, allowing the user to move into the cleanroom as contaminant-free as possible. That initial step of entering an air shower to remove particles from the people or objects entering the cleanroom, allows the cleanroom filters themselves to work at as high an efficiency as possible, ensuring that the cleanliness level of the cleanroom and the project within it are maintained.
We feature a full line of air showers here at Liberty Industries, and we can also build to your custom requirements. Contact us for more information! To see an air shower in operation, watch this video.
[youtube https://www.youtube.com/watch?v=Y-WYuIE57rk]
This video from NASA shows some final steps in preparing spacecraft – everything from shuttles to satellites – to be launched into orbit. What is the most important part of this final check? The fact that it occurs in a cleanroom. As you know, there’s plenty of preparation for a person to enter a cleanroom as well: the Tacky Mat®, a shoe cleaner, a “bunny suit”, and an air shower. All of these steps appear in the video – and each of these products can be manufactured or supplied by Liberty Industries.
Of course, we’re pleased to be working with NASA, and the video did a great job of giving a quick and easy overview of the importance of cleanrooms. There’s a lot more to cleanroom protocol than what you can see in the video. From filtration units to laboratory equipment itself, there’s so much that goes into keeping the cleanroom clean, and Liberty can provide all of it. We take contamination control seriously, whether it’s for NASA, one of our Fortune 500 clients, or our next new customer, potentially you. Contact us with any further questions!
There are some projects that just about anyone can do, with a trip to Home Depot, a weekend in the garage, and a familiarity around a toolbox. But some tasks require a level of expertise and specialized knowledge that the layperson just does not possess. Yet in recent times, the “DIY” approach to designing almost anything under the sun seems to have taken hold regarding any task, however complicated and out of the “backyard project” scope it may be.
Where did the rapid expansion of this mentality come from? The difficult economic times of the past few years play a role, to be sure, and so does the sheer volume of Complete Idiot’s Guide manuals in stock online and on bookshelves. And if those kinds of books don’t do the trick for you, you can watch a YouTube video or read an eHow article and have all your home improvement questions answered in a few minutes. While we at Liberty Industries have no problem in theory with this sort of problem-solving, we also know from years of personal experience that a DIY approach can’t come close to successfully building a facility as complex as a fully-functioning cleanroom.
Just as building a rocket that can make it into space requires an actual team of rocket scientists, building a cleanroom requires a qualified cleanroom design engineer. This engineer and anyone working under his or her supervision must be alert to any challenges and difficulties that lie between receiving a design and list of requirements, and successful completion of the cleanroom.
The design and construction team’s expertise also is not limited strictly to knowledge of contaminants – they wear many hats. They must be literate and experienced in the design of HVAC systems, and how those systems contribute to the successful maintenance of atmospheric conditions such as humidity, temperature, and pressure. They must act as architects, and be familiar with what sort of floor plan might best be employed at the particular facility in order to ensure adequate contamination protection (i.e. should, or could, the cleanroom have an antechamber or gowning room installed that allows workers to leave their “contaminated” day-clothes behind?) They must be well-versed in the properties of the materials used in building the facility, and whether these materials are appropriate to be used within such an environment. These are just a few examples of the questions that a qualified cleanroom engineer must ask him or herself before agreeing to build such a facility.
We certainly do not mean to discourage thoughtful “do-it-yourself” design in general. Out-of-the-box thinking certainly has useful and essential applications. That being said, the science of cleanroom design and fabrication is tried and true, but remains a challenge to many who would attempt it. With many decades of experience in this field under our belt, we at Liberty Industries do feel entitled to say it: leave expertise to the experts. You’ll never regret the results.
Since 1953, Liberty Industries has been in the business of designing, building, and perfecting new contamination control technologies and strategies. Through nearly six decades of careful and consistent effort, we have accumulated a time-tested track record in building products that assure the necessary contamination controls in work environments that require them. Products that started out as one-time, custom designs have developed gradually into whole lines with a host of specific applications.
One product line that we are especially proud of fabricating is our new PureSeal Pass-Thru series. Pass-thrus are an existing technology, and basically operate hand-in-hand with a cleanroom. Pass-thrus are units that allow for products or materials like laboratory tools and medical instruments, as well as products being manufactured to “pass through” from a contaminated environment to a cleaner ISO 14644-1 specified cleanliness level. To that effect, we offer various pass-thrus that apply different shapes and/or sizes, as well as materials of construction, toward that overall goal.
Liberty’s PureSeal Pass-Thru is intended for use in such areas as research university and biotechnology laboratory settings. Applying lessons learned over many years, the PureSeal performs its task of keeping exterior contaminants away from the interior cleanroom environment. Comprised entirely of easy-to-disinfect, electropolished 304 stainless steel, and employing a custom monolithic PureSeal gasket that allows for steam cleaning, the PureSeal is uncompromising in terms of its protective ability. An isolated mechanical interlock adds one more line of contaminant separation, ensuring that the interior and exterior doors of the PureSeal can never be open at the same time.
Help us to do a better job in providing innovative, state of the art products for scientific research and development. Feel free at any time to contact us with suggestions or just to let us know how you’ve applied our products to perform your job.
establishing a cleanroom rating of ISO 1-9 based on those factors. As you know, cleanroom users and engineers will typically refer to a room as an “ISO 4,” “ISO 5,” and so on. While lower numbered ISO specs require the full complement of coveralls, shoe covers, and similar garments, higher numbered rooms like an ISO 9 can be entered in garments like a frock covering everyday clothes.
