This week, especially because it’s December and so close to the Christmas holiday, I worked on an alarming application that involved a static hazard. 100% ethanol was poured from a plastic container, which held approximately 5 gallons of the liquid, into smaller or larger containers that were also made of plastic. Ethanol is a colorless, volatile liquid. Most people recognize it as the ingredient in liquor, which has an intoxicating effect on most people. However, it is also used as a solvent which can ignite under certain conditions. Static electricity is one of the three components necessary to create an event, which is a soft way of saying an arc-over, a fire or an explosion. The other two ingredients are oxygen and a volatile vapor.
There are well established protocols for handling and working with ingredients that can go “boom in the night”. The front line of defense in protecting oneself from mishaps is grounding everything that is capable of being grounded. If we take a simplistic approach and look at the world as being made of only two materials, insulators and conductors, you can get a better sense of safety procedures that will keep to us out of harm’s way. Metal is a conductor and easily grounded by clamping onto a known building ground or electrical ground or even by driving a rod deep into the earth. Hence, we call it an earth ground. A water pipe inside of a facility can also act as a good ground source. By grounding the metal, electrons can flow through the metal to ground itself. Conversely plastic cannot be grounded. This is why my static application hit a bump in the road. Static is generated on plastic materials through friction which we call Tribocharging. There are a myriad of types of plastic, but for the most part, assume that all plastics are huge static generators. Plastics are insulators and not conductive so the energy generated by simply handling plastic stays on the surface and can be a source of ignition.
In my static hazard application, an ungrounded person holding the ethanol picks up an ungrounded plastic container and pours it into another ungrounded container. This is not a good situation. During the pouring process, a potentially explosive, volatile vapor cloud forms around the pouring action in both the dumping container and the receiving container. There are three possible opportunities that can cause ignition in this scenario: a discharge from the ungrounded tech who is pouring the flammable ethanol; a discharge from static on the container which is high enough in proximity to the vapor cloud which forms in the discharging plastic container; a discharge from static to the same cloud that can form in the receiving plastic container. If a static charge is present, with enough energy behind it, there is a strong chance that any of these actions can create a safety hazard.
A Grounding Solution
Finding a solution to this problem can be a bit tricky. The basic approach is to ground everything that can be grounded or switch to materials that can be grounded. Simply switching from plastic containers to metal is a huge step in the right direction. There will be times when grounding is not possible and materials cannot be changed. In that case, ionization is the only choice. There are approved ionizing static bars and blowers that remove or greatly reduce static electricity on plastic materials. Static Clean and Fraser AntiStatic Techniques of England have formed a strategic alliance / partnership to address these dangerous scenarios. When you have concerns about your facility and the safety of workers who may be in harm’s way, please reach out to Static Clean for help. At this special time of year as with any time of year, it is important to always think “safety first”.
How do you know if your Thanksgiving stuffing is actually clean?
As we approach the Thanksgiving Holiday in the United States of America – it got me to thinking of how static electricity and contamination might affect my holiday food & meal preparations. I know you probably say, “Who thinks of that and why?” but it’s the nature of my job and our company, so it’s always in the back of my mind.
When you unwrap packaged food (turkey, stuffing, cranberry sauce, yams, pie crust, etc.) – how do you know that the package your food comes in is clean? The simple answer is that the normal person doesn’t know. That question of cleanliness is just assumed by the consumer, but the normal person doesn’t really think about whether or not the package their food is in is uncontaminated. The FDA tries to setup requirements and mandates but they are so small in comparison to regulate it that companies fall between the cracks and it’s not until you read or hear about it on the news. By that time it’s too late. There is an interest read on the FDA website about the requirements and steps required to package food.
Contamination in the food packaging industry
In the food packaging industry – static & contamination can be a huge problem. In particular – plastic packaging. All the rage these days is for packaging to say, “BPA Free”, right? Bisphenol A (BPA) is an omnipresent compound found in plastics. It is a fundamental ingredient of plastics from polycarbonate to polyester. An article in Scientific American (*www.scientificamerican.com) says, “BPA is routinely used to line cans to prevent corrosion and food contamination; it also makes plastic cups and baby and other bottles transparent and shatterproof.” Insert your shocked face here! No wonder why plastic and packaging companies are working so hard to provide us with “BPA Free” packaging and products. Makes you wonder what your canned yams and cranberry sauce at Thanksgiving are packaged in, doesn’t it? The second point regarding plastic packaging is that particulates tend to stick on plastic materials if the plastic has not been static neutralized. If the plastic packaging has not been static neutralized – particulates – usually loose, dry contaminates (and food; i.e. your stuffing) will attract to the plastic. Prior to packaging – you may have contaminates that stick to the plastic or bag – so that is an issue. Also, if the plastic is sticking to itself and not opening up enough during the filling process, then the product being packaged (i.e. stuffing) will stick to the sides as well as the outside or top of the plastic PRIOR to it being heat sealed shut. That is why static & contamination control is an integral part of the packaging industry.
This year – I am THANKFUL for static control and contamination control products manufactured and sold by Static Clean to packaging companies. Without such technology that allows us to neutralize and control static and particulates in the packaging process – I may be eating stuffing a la mystery meat. It gives entirely new meaning to “Stuffing” doesn’t it?
I was chatting with a friend/customer the other day and asking him if he was still playing hockey in a men’s no-check league. His response was that it was “time to hang it up”. It got me to thinking about all the things we do in life where we can use or connect that phrase.
The obvious meaning of hang it up is to stop doing something that you’ve done for a long time. How about hang it up as in hat, coat, phone, pictures, and decorations. The gloomier side of the phrase can mean break-up, bring to a close-like a chapter in one’s life- and cease, which has very strong connotations, but the one that I like the most is “bag it”. Many of us have used the phrase, “why don’t you bag it” on people we know. From watching detective TV shows involving criminal investigations and forensics, “bag it” refers to putting evidence in a sealed bag or container.
Plastic, All Wrapped Up?
There are many kinds of bags and containers that are produced every day in factories throughout the world. They can be either converted film, blow molded containers, injection molded boxes or cast materials, but can you imagine not having a plastic storage bag or container to keep food in the refrigerator? While we all try to be “green”, the plastics converters are working to make improvements with bio-degradable, engineered materials, but the reality is that plastic bags and containers are creature comforts that make our lives easier and will be around for a long time.
Most plastics come from petroleum based resin, that by the time it becomes a finished product on the various machines, it has been subjected to high amounts of static electricity. These unwanted static charges can cause defect in the materials, lost production because of having to run the equipment slower than possible, particle attraction which reduces quality and jamming in the process, which causes down-time and lost profits. Static Clean provides many types of ionizing air products that reduce the ill effects of static electricity. They are available in the form of static bars, blowers, nozzles, air knives and cleaning systems.
In time, the choice of materials will lean more towards environmentally friendly resins that may not cause static levels that are harmful, but until then Static Clean can help improve the process, because most of us would have to agree that it is not quite time yet to “Hang It Up” when it comes to creature comforts like plastic bags.
What’s in a name? Customer have always considered the name, “Static Clean” to be synonymous with producing products that clean sheets and webs in the Converting Industries. For many years, our company has been manufacturing WebVAC Systems that achieve the cleaning criteria that many customers expect. How clean is clean? The cleaning level or efficiencies that are reached with the Static Clean- WebVAC and similar systems is a 95% success rate in the 25-30 micron range.
Raising the Bar
With multi-laminations, higher cleanliness standards of materials used in notebook, laptop, television screens, finer lines of resolution in printed circuit boards, and the growing medical device packaging market, the bar has been raised. Demands have been placed on suppliers to deliver sheeted or web based paper and plastic materials that contain less debris, or what is now called Foreign Matter (FM).
A Higher Standard of Clean
In an effort toward continuous improvement, Static Clean has partnered with Polymag Tek. What’s in a name? Polymag Tek’s original business model was to provide materials and equipment to clean magnetic tape. Does everyone remember magnetic tape? Back around 1928, magnetic tape was invented in Germany to record sound. In the 1950s and 1960s, magnetic tape was widely used by IBM in the storage of computer data, particularly for backups. In the 1990s, the pressure was on to store even more data on mag tape and it meant making sure that the surface of the tape was totally clean. How clean is clean now?
Polymag Tek’s Contact Cleaning rolls and equipment achieved cleaning levels down into 10 microns and below beginning in 1994. For a greater understanding of the technology, please visit their website by the following link to their “Dirt Report”
For information on their full line of hand rollers, web and sheet cleaners, as well as process roll cleaners including the water wash systems, please visit their website at www.polymagtek.com.
Tribo-Charging, Who Really Discovered Electricity?
The relationship between static electricity and particle attraction has been long known. The Ancient Greeks when polishing their jade and precious stones noticed that straw, chafe and other particles were attracted to the exact things they were trying to clean, the family jewels. This phenomena became known as “Tribo-charging“. Simply stated it was the contact and friction that generated an electrostatic field around the parts that attracted the debris.
The Plastic Attraction
In the Life Sciences Industry of today most companies use plastics in their process. Whether it is to replace body parts, catheters, injection systems, pumps, blood separators or their packing, plastics are here to stay. Not only are they here to stay, but plastic is being used in this process at an increasing rate. Most of these engineered plastics are for a specific need but the premise is the same, they generate huge amounts of static that causes Foreign Matter (FM) to be attracted to the products and the process.
Medical Device Manufacturers most often individually package each medical device and they are subjected to 100% inspection. When the inspector sees a speck of debris (FM), which could be in the form of plastic bits, fuzz balls from clothing, or even human hair, the package is then ripped open and put aside for repackaging. These units are tracked in what is generally called “the tear down rate”. In almost every case, the root cause was the forces of static electricity pulling unwanted particles onto the product and the packaging materials. In addition to the packaging level there are various stages in the assembly process where FM causes rejects. Some of those stages include Injection Molding, Coating, Ultrasonic Welding, Bonding/Gluing, Forming, and handling during the assembly processes. These are also key functions that need to be addressed. The common denominator being that contact and separation (tribo-charging) occurs, static is generated and FM comes into play to contaminate products that could end up inside the human body or blood stream. The FM could also potentially block injection or fluid systems clogging pathways designed to deliver medicine.
Gains are Being Made, Reducing FM
The front line of defense is a properly maintained clean room, but that doesn’t address process problems at the local level, aka the workstation or cell. How does static control reduce particles via ionization in the fight to reduce FM? Static Clean did a job last year for a major medical device company that was experiencing a very high tear down rate. They approached us to come up with a system where they could pass their products thru a blow-off, ionized, vacuum table. The results of this first system allowed them to run 50,000 parts without a single tear-down.
While not all medical device manufacturers have identical assembly lines, let’s take a look at the types of static controls are that implemented for specific reasons or points in the process.
Room Ionization: In this installation, ionizers are mounted in the ceilings and the preferred method is to locate the ionizer right under the Fan Filter Unit. (FFU) to take advantage of the clean air being delivered into the room.
The Increasingly popular approach has been to use source capturing methods in conjunction with ionizing air tools. Recent gains have been made in the development of customized medical cleaning workstations that meet clean room protocol and are tailor engineered to a specific product or package.
Who doesn’t like FM when it comes to listening to the radio? In the world of music, FM stands for Frequency Modulation, a method of broadcasting electrical signals. In a short blog, it is difficult to fully explain FM, but there are online tutorials and videos that explain how Frequency Modulation works in relationship to the amplitude and phase remaining constant, while the frequency is changed because of the signal input.
In the world of Medical and Pharma Packaging and Processing, FM has a totally different meaning. Foreign Matter (FM) is the cause of contamination, poor yields, rejects, rework and the total recall of products once in the field. The FM can be particles in the form of lint, clothing, skin flakes, hair, and dust. Another form of foreign matter particles are bits of plastic chips and slivers of angel hair which come from the plastic forming process, especially thermoforming.
The Life Sciences Industry as a whole spends huge sums of money to construct clean rooms that, by design, are supposed to keep foreign matter out of these processes. This assumes that the room is always operating at full efficiency, that humidity and temperature are being controlled, and that everything and everyone that enter the clean rooms are particle-free. That, of course, is not reality, especially if the clean room is not up to semiconductor level protocols, with strict adherence.
The Missing Equation
The missing part of this equation is ionization, whether passive or active, room type of systems or local ionization with source capturing abilities. Static electricity by nature not only attracts particles, but holds them securely to any plastic substrate. Plastics have been the widely used in the manufacturing of medical devices and their packaging is almost always some form of plastic that includes bags, pouches and molded trays. When you rub a balloon, you can pin it to the ceiling with static electricity. When a plastic part of a package generates static by handling, it has the ability to violate the process of keeping the environment Foreign Matter (FM) free.
That reminds me of the bridge in a Steely Dan hit and the line in the song goes like this, “FM –no static at all”.
If you want to reduce foreign matter (FM) and the root cause, “static”, Static Clean can get you to no static at all. Contact our tech sales team today and find out how we can assist you meet your goals.