Particle Size, Particle Retention & Process Practicality

Particle collection efficiency by a filtration device usually brings a common question. What is the ISO number that is associated with HEPA filters used in the Static Clean Particle Trap® series products? A recent request from a customer asked this exact question. Our answer in response was that the ISO rating on our HEPA Filter is ISO 40E-99.99% at MPPS. Obviously, the customer with the questions knew what to ask and was technically astute, but to a novice it may seem confusing, so first let’s establish what MPPS mean. It is the Most Penetrating Particle Size. Larger particles are unable to avoid the special filter media in a HEPA filter and they become embedded in the filter material. The smaller particles become the MPPS, which gives the HEPA their rating. For more critical filtration needs, ULPA filters are available and could have an efficiency of 99.99995% at MPPS.

For the world of static control, and filter efficiency of the Static Clean Particle Trap® Systems, we are mostly talking about HEPA filtration. But filtration only tells a part of the story. Although you can perform tests to validate HEPA filters and modern particle counters can provide information on airborne particulate, it doesn’t tell the story on how clean a medical injection molded plastic part may be or how many particles are on a catheter or the tray or package that is going to house the medical device. Yes, there are liquid particle counters that can verify all particle sizes, but real time production of high-volume parts means that, at best a visual inspection on the fly is the standard.

Most of the Medical Device Manufacturing is done in an ISO Class 7 or ISO Class 8 cleanroom, with an emphasis on ISO Class 8. Federal Standards FS 209E and ISO 14644-1 require specific particle measurements to verify the cleanliness of the clean room or clean area. When talking about an ISO Class 8 environment, it does mean that the maximum/particles/m3 allows for almost 30,000 particles in the 5 micron or smaller range. It also means two other things as well. There will be particles greater than 5 microns in an ISO 8 space and that total reliance on a cleanroom is not the complete answer. The use of additional filtration methods at key points in the manufacturing process will improve yields by reducing particles on products and in single use packaging that may finds its way to the hospital or clinic. The fact that ionization is used to control static on medical devices, optics and industrial environments is common knowledge, but, source capturing debris at critical stages in the process is less understood but becoming more accepted as the right tool at the right time.

Particle Trap® products are small, benchtop or floor level source-capture systems, that incorporate both pre-filters and HEPA-filters in series, whereby the pre-filter catch the larger particle and the HEPA, (the same used in the clean room construction), captures the smallest debris. What this means for the customer is that particles are taken out of the room at the source and by source, either where they are created or where they can do the most harm and end up inside of a finished package. Regardless of what ionizing blow off device is used in your process, you can rely on Static Clean to make things cleaner and your customer smile.

Where do the particles go?

Did you ever rub a balloon on your hair and stick it to the ceiling? The balloon sticks because you’ve created static electricity on the surface of the balloon. This energy is non-moving static charge. Every material is made up of atoms and they are the basic building blocks of ordinary matter and they can join to form molecules, which is a basic ingredient of most of the objects around us. An atom can hold a positive charge that is called a proton or a negative charge that is called an electron. Atoms with the same charge or polarity repel each other, while those with the opposite charge are attracted to each other. Just like the balloon scenario, static is created by the contact and separation of two materials. The same is true of when you walk across a carpet and touch the metal door knob and get a shock. We call these electrostatic forces, tribo-charging, which renders a plastic material in a state where it can attract dust and other particulates.

Let’s face it, we are using more plastic in our every day lives, from cars to single use medical devices that may end up inside of the human body. Plastic, being highly insulative, can store huge amounts of static electricity. If we just look at the medical device sector, one of the biggest reasons for rejects, rework and potential device failure, is from foreign particles that end up in the finished device. These particles could be in the form of airborne contaminants, plastic flash, skin flake, human hair and other debris that is found in the manufacturing process. Static eliminators in the form of ionizing air guns, nozzles and ionizing blowers are used to negate the ill effects of electrostatic forces that pull particles right out of the air and hold them to a device or components. The use of ionized air is absolutely a good practice, but the problem is “where do the particle go”? Typically, they hang around and end up on the work surface to be a source of re-contamination or the particles end up downstream on already cleaned products.

Enter the Particle Trap® 6000. The Particle Trap® 6000 (PT6000) is the solution to getting rid of particles in the assembly and packaging areas of the medical device manufacturing process. The PT6000 is a source capturing system with a HEPA filter on the exhaust. You can still use the conventional ionizing air blow-off devices, but when working in front of the opening of the PT6000, dislodged particles now are delivered through a pre-filter and then through the HEPA filter, ensuring only clean air is let back into the room. The PT6000 is used not only to clean medical components, but it is especially helpful when used at the packaging level, just prior to the heat sealing of a lid stock to the thermoformed tray. The same would be true for pouching of products such as a catheter on a die cut card being slid into a long plastic bag and then sealed at the end. Normally, most medical device manufacturers do a 100% inspection for foreign matter/particles inside of the seal trays. If a particle is discovered, the lid is ripped off, the product taken out, recleaned and then repackaged. This reject rate is also called the tear down rate, which translates into poor yields, time and money along with customer dissatisfaction, when a product gets through that is not totally cleaned.

Who would benefit from the Particle Trap® 6000? The Particle Trap® 6000 and its sister products, the PT Mini, Particle Trap® CUBE and Medical Cleaning Systems. While the medical device sector has endorsed these products, they also have application in the optics, food and electronics industries for the same reason why all companies are looking to lower their tear down rates, which translates to higher profits. If you want to learn more about how Particle Trap® products can help improve your process, please contact our technical sales team for more information.

Introducing our NEW “Clean & Pack,” Don’t Look Back!

Let’s face it, the Medical Device Manufacturers have come under scrutiny, not only from their customers, but also from the FDA in an effort to create a manufacturing environment that has less particulate which can impact quality.  Static Clean International manufactures static control and particle source-capturing products that aid in this effort by reducing particles at critical points in the process.  Three of the most critical areas in the process are at the molding, assembly, and packaging stages of these medical devices. Packaging is the primary source of foreign particles in the process.  Remember, these packages are going to house a medical device that eventually ends up at a hospital or a clinic for use on patients where “clean” is critical.

Medical Clean Room Test Environment

Customers ask us how well our Medical Cleaning Systems work and to what level our “Clean and Pack” system helps to reduce contaminants.  In an effort to guarantee success, Static Clean International recently installed a brand new ISO Class 7 Clean Room that is fully equipped with products that are designed to reduce particles, lower rejects and improve yields.   Customers are invited to visit our facility, bring their trays or devices into our clean room, and learn first-hand the value that Static Clean and its products bring to the Medical Industry.


All That Glitters Is Not Gold


“All That Glitters Is Not Gold” —  Not everything that is shiny and superficially attractive is valuable.


Cleaner Means Safer..

Sometimes the smallest parts are the trickiest to clean.  At Static Clean our customers often bring us size challenging parts and devices to work on. Until recently no one in our industry has been able to address these challenges. Static Clean has now developed a method using our Medical Cleaning Station and Medical Cleaning Station-AS cleaning benches to batch clean these small part products. We have a Stainless Steel sieve that is fed through the upper and lower hoods that are part of our MCS line.  We had a potential customer from New Jersey who was amazed at how well it worked. Before he arrived, he went to a Michael’s store with his daughter and bought all kinds of colorful glitter that you would use for arts and crafts.  He used the glitter to contaminate the white caps that you see in the video.  It was overkill but a very good test.  The white caps that you see here go on the top of things such as suspension bottles, eye drop bottles, contact lens cleaning bottles etc.  If they have particles, plastic bits, human hair or any foreign matter, it could be the cause of a health problem.   Our batch cleaning system worked so well that he has said he is interested in purchasing not one but two MCS Systems and commented that “it worked better than I ever anticipated”.

For more information on our MCS or MCS-AS Cleaning benches, contact our technical sales department today.

Controlled Turbulence in the Clean Room

Most Clean Room experts and consultants cringe at the thought of having turbulence inside of a clean room or clean space even though it is a necessary evil. Compressed air driven ionizing guns and nozzles are indeed a requirement to get rid of particles in the process, on the product itself and worse yet inside of the package.  Particles typically show up after heat sealing the lid in place. How do you make a process cleaner and reduce waste without the use of ionizers that use compressed, Clean Dry Air (CDA) or Nitrogen (N2)? The simple answer is that you go with whatever blow-off device is required, but control the turbulence.

What does turbulence have to do with a Clean-room, you might ask?  Unlike laminar air flow, turbulent air flow is not channeled in smooth parallel paths but distorted or agitated.  Typically this dilutes the contamination but it can also distribute it across the whole clean-room.  Wikipedia’s definition of a clean room is this; A cleanroom or clean room is an environment, typically used in manufacturing or scientific research, with a low level of environmental pollutants such as dust, airborne microbes, aerosol particles, and chemical vapors. More accurately, a cleanroom has a controlled level of contamination that is specified by the number of particles per cubic meter at a specified particle size.

The basic problem associated with the use of turbulent air tools is “where do the particles go”? The answer is quite simple; source capture the debris where it is being created. With the right containment equipment in place, the dislodged particles can be drawn into a filter media that greatly reduces the risk of re-contaminating the products just cleaned or dumping the particles on the nearby manufacturing cell. The hotspots where particles are created may be at the molding machines, ultrasonic welding stations, de-burring, assembly, packaging or other points of friction where static is generated.

The best solution for companies dealing with these problems, especially the applications that involve medical packagers is to incorporate an ionizer into the source capturing equipment or use ionizing in conjunction with a means to capture the debris. Static Clean can offer both solutions. If you are using an ionizing air gun to remove particles, it only makes sense to use the Particle Trap® to capture those particles.   If the same problems apply and the desire is to take human error out of the equation, the answer is to use a Medical or Parts Cleaning Station that we offer in both manual and automated models. View the details about the Particle Trap® 6000 and our Medical Cleaning Stations-MCS-AS.

Every Opportunity is an Opportunity

Sir Winston Churchill, as Prime Minister of Britain was faced with the daunting task of leading his country from the brink of defeat to victory. He is noted for many quotes and speeches around 1940 including “Blood, Toil, Tears and Sweat, and “We Will Fight on the Beaches” but none is more famous than the “This Was Their Finest Hour” speech to the House of Commons on June 16, 1940 just one month after he became Prime Minister. He is also credited with the following quote along with many others.

“A pessimist sees the difficulty in every opportunity; an optimist sees the opportunity in every difficulty.”  -Winston Churchill

Is your glass half-full?

Another way of describing people’s attitude in life is the difference between the glass is half empty full vs. the glass is half empty. Churchill, born in 1874 had a good genetic combination that made him the right choice to lead the United Kingdom at a very difficult time in history, especially with Europe under siege by Hitler’s forces. He was a military man who had a British statesman father and a New York born, independent thinking, socialite mother. This combination brought him to the forefront as the right man at the right time in history for not only the British people, but for Europe and the world.

In business, we all want to be optimist and not dwell on the things that are wrong or business that we lost to China or more to the point, complaining about things out of our control. We need to focus on the positive and what we do well to be competitive in the Global Economy. If Churchill hadn’t maintained a healthy attitude and rallied the troops to save his county, what do you think the end result would have been? The landscape of Europe would look much different today. President Roosevelt and Churchill though very much different in so many ways, found a way to work together. Many people believe that the government work programs of the New Deal was the key to our vital economy and getting out of the Great Depression, but it was more about the destruction of the infrastructure in of so many countries including Europe and Japan that made America the strongest economy in the world.

Attitude is everything

The United States with its raw materials and a ready and willing; post- war workforce was up for the challenge. By 1944, the unemployment rate in the US was 1.2%, still the lowest in American history. Even with our military personnel returning from the war, the unemployment rate stayed under 4% throughout the 1940’s. You can see why panic sets in when the US unemployment rate get above 8%. The population of the US in 1944 was less than 140 million people and in 2014, it is 317 million. The math shows a clear picture of our country moving in the wrong direction. How do we turn things around? I asked a very liberal friend the other day a simple question. If you had to pay $10.00 more for a pair of sneakers made in the USA instead of a plant in Asia, would you? His answer was absolutely not and he justified it by saying that it was his job to get the best price possible. If we had a level playing field it might be different, but the US tax burden and regulatory compliance means higher costs to produce goods. Notwithstanding the attitude of my misguided friend, there is a huge under swell of buy American sentiment going on and many companies that went to China are moving manufacturing back to the States. We won’t get it all back, but we will see better days ahead. The bright spot in our manufacturing sector is Medical Device Manufacturing and Static Clean with its key products such as Hepa-Clean Chambers and Medical Cleaning Stations is seeing the benefits from every opportunity presented. Visit us at Static Clean for information on our products. Our hope is for more Americans to think globally, but act locally and hasten the return of American entrepreneurship.