Is It Safe To Use Compressed Air?

Think about it…compressed air is, by definition, gas under pressure: potential (stored) energy.  This energy is intended to do work, like operation of pneumatic tools, actuation of pneumatic cylinders, debris removal with an air gun or blow off device, and (even though I haven’t done it in a while) my personal favorite:

High pressure compressed air is meticulously made, prepared, and stored to ensure the number of surfaces equals the number of dives.

Uncontrolled, unplanned, or accidental releases of stored energy (regardless of the source) are inherently dangerous, and great care must be taken to guard against such incidents.  This is accomplished, primarily, in three areas:

*Operation.  This might be the most prevalent, because it involves the greatest number of personnel (e.g., everyone) as well as the ways compressed air is used (e.g., all of them.)  It’s also the area where the most involved people (the operators) have the most control:

  • Personal protection.  Don’t even think about operating a compressed air device without eye protection.  Ever.  Hard stop.  Also, if the operation involves flying debris, a full face shield, long sleeves, gloves, etc. might be called for.  Hearing protection may be required as well…keep in mind, even if an engineered device (like any of EXAIR’s Intelligent Compressed Air Products) generates a relatively low sound level, the impingement noise of the air flow hitting the object can reach dangerous levels.
  •  Personnel cleaning is prohibited.  The risk of injury to the eyes, respiratory system, and other parts is just too great to rely on personal protective equipment that’s designed for use while discharging compressed air AWAY from the body.  While this is expressly prohibited in certain situations, OSHA has long recognized it as good practice for all industries.
  • No horseplay.  ’nuff said.  Plenty of better ways to have fun at work.

*Design.  This one usually has the advantage of being traceable to a small number of people, and is also the one that’s most likely to be documented.  This is where it starts…if the system is designed to fail, it doesn’t matter how much care the operators take:

  • Supply lines, fittings, and hoses must be rated for use with compressed air, up to and exceeding the maximum discharge pressure of the air compressor.
  • This goes for any tools, blow off devices, components, etc., serviced by the air system.  The only thing worse than a component failing is a component failing in your hand.
  • Shut off valves should be located as close as practical to point(s) of operation.  This allows you to quickly secure the flow of compressed air to a failed component, hose, etc., and prevent further damage or risk of injury.
  • Hoses shouldn’t be run across the floor, where they can become a trip hazard or subject to damage from stepping on them.   This is a surefire way to find out the value of shut off valves (see above.)

*Product specification.  Or, more simply put, using the right tool for the job.  A broader discussion could include efficiency and performance, but we’ll stay within the confines of safety for the purposes of this blog:

  • Be mindful of dead end pressure.  Blow off devices, especially hand held ones like air guns, are oftentimes fitted with a simple open-end discharge.  If this is pushed into a part of the body, the pressurized air can break the skin and cause an air embolism.  This is a serious injury, and can be fatal if it reaches the heart, lungs, or brain.
    • This is a key consideration to OSHA Standard 1910.242(b), which limits the downstream pressure when compressed air is used for cleaning to 30psi.
    • EXAIR products are compliant with this Standard by design…there’s always a relief path for the air pressure; they can’t be dead ended.
Because the compressed air exits through a series of holes, recessed between a ring of fins, any attempt to block the air flow will simply send it in another direction.
  • Harmful sound levels are a consideration as well.  As stated above, hearing protection is required in many cases, but sound levels can be mitigated through the use of engineered products.  EXAIR Intelligent Compressed Air Products, as a result of their high entrainment, generate a boundary layer of air flow that leads to dramatically lower sound levels than a similar-sized open end blow off device.

If you’d like to explore ways to make your compressed air system safer, give me a call.

Russ Bowman
Application Engineer
EXAIR Corporation
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Standards, Compliance, And You. And EXAIR.

I’m pretty impressed with the number of safety features my car has. Aside from the literal lifesaving functions like seat belts and air bags, it’s got anti-lock brakes…if you’ve ever had to counter-steer out of a skid on an icy road, you will appreciate the value of this for sure.  Those are just some of the ones I’m keenly aware of – the Federal Motor Vehicle Safety Standards comprise dozens of regulations in three categories: crash avoidance, crashworthiness, and post-crash survivability.  None of these prevent me from operating my vehicle at an unsafe rate of speed…an expensive reality that an Ohio State Highway Patrolman dutifully reminded me of last Sunday afternoon.

Likewise, there are many regulations to ensure safety and prevent hazards of all kinds in industry, administered by a host of agencies that are either subordinates of, or accountable to, the federal government.  When you manufacture products that are used with high energy sources (compressed air or high voltage electricity,) a strong commitment to safety is not negotiable.  So, at EXAIR, we commit considerable resources towards the best engineering and manufacturing practices to make our products as safe as possible.  That includes compliance with a number of standards and certifications:

The Occupational Safety and Health Administration (OSHA) is an agency of the U.S. Department of Labor.  Their mission is to “assure safe and healthful working conditions for working men and women by setting and enforcing standards and by providing training, outreach, education and assistance.”  They are a regulatory body in the truest sense, in that they don’t offer certification or approval of products, processes, etc.; they publish guidelines and standards for manufacturers and users to comply with.  OSHA Standard 1910.242(b), for instance, limits the downstream pressure of a compressed air operated device used for cleaning purposes to 30psi. Now, you can regulate the supply pressure to meet this, but that also limits the effectiveness of the air flow generated.  EXAIR Intelligent Compressed Air Products are all designed and manufactured to be in compliance with this standard, at any supply pressure.  Take, for example, our Super Air Nozzles:

Because none of our products can be dead-ended, there’s always a relief path preventing the downstream pressure from exceeding that level.

OSHA also has Standard 1910.95(a), that sets limits for maximum allowable noise exposure.  All EXAIR Intelligent Compressed Air Products, with the exception of some our largest and most power Super Air Nozzles (which aren’t normally used in areas that don’t already require hearing protection anyway) meet the 8-hour exposure limits of this standard.

Hearing loss is the best known, but not the only, ill effect of harmful noise exposure. It can also cause physical and psychological stress, impair concentration, and contribute to workplace accidents or injuries.

CE marking indicates conformity with health, safety, and environmental protection standards for products sold withing the European Economic Area.  Unlike OSHA standards, responsibility for CE marking falls solely with the seller of the product – a CE marked product has been tested and certified to have been made in such a way to meet safety & quality benchmarks specified for that type of product.  All EXAIR products that are defined under applicable directives have been tested according to these standards, and carry the CE mark.

The Restriction of Hazardous Substances Directive, or RoHS, is another standard borne from the European Union, and is geared towards public & workplace safety by restricting the use of hazardous materials in the manufacture of electronic & electrical equipment.  Since its inception in 2006, similar standards have been vigorously adopted around the globe.  Electrical portions of EXAIR’s Static Eliminators, EFC Electronic Flow Controls, ETC Electronic Temperature Controls, Digital Flowmeters, Solenoid Valves, and Thermostats all comply with the RoHS Directive.

Section 1502 of the Dodd-Frank Wall Street Reform and Consumer Protection Act doesn’t address a concern for product users, but rather a particularly troubling human rights issue – Conflict Minerals.  For almost two decades, trade in tin, tantalum, tungsten and gold in the Democratic Republic of the Congo (DRC) has been used by some very bad people to finance violent campaigns against their neighbors.  EXAIR thoroughly and systematically documents our supply chain compliance with this act.  We are proudly committed to our support for this effort to the world a better place for everyone…especially those in desperate circumstances beyond their control.

EXAIR Intelligent Compressed Air Products have been successfully implemented into a variety of uses where application- or industry-specific standards are in force.  We’re happy to work with you to determine if our products meet those standards…or can be made to meet them.  If you’ve got such an application, give me a call.

Russ Bowman
Application Engineer
EXAIR Corporation
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Heat Transfer – 3 Types

When you have two objects and they are of different temperatures, we know from experience that the hotter object will warm up the cooler one, or conversely, the colder object will cool down the hotter one.  We see this everyday, such as ice cooling a drink, or a fan cooling a person on a hot day.

The Second Law of Thermodynamics says that heat (energy) transfers from an object of a higher temperature to an object of a lower temperature. The higher temperature object has atoms with higher energy levels and they will move toward the lower energy atoms in order to establish an equilibrium. This movement of heat and energy is called heat transfer. There are three common types of heat transfer.13580963114_f222b3cdd9_z

Heat Transfer by Conduction

When two materials are in direct contact, heat transfers by means of conduction. The atoms of higher energy vibrate against the adjacent atoms of lower energy, which transfers energy to the lower energy atoms, cooling the hotter object and warming the cooler object. Fluids and gases are less heat conductive than solids (metals are the best heat conductors) because there are larger distances between atoms.  Solids have atoms that are closer together.

Heat Transfer by Convection

Convection describes heat transfer between a surface and a liquid or gas in motion. The faster the fluid or gas travels, the more convective heat transfer that occurs. There are two types of convection:  natural convection and forced convection. In natural convection, the motion of the fluid results from the hot atoms in the fluid moving upwards and the cooler atoms in the air flowing down to replace it, with the fluid moving under the influence of gravity. Example, a radiator puts out warm air from the top, drawing in cool air through the bottom. In forced convection, the fluid, air or a liquid, is forced to travel over the surface by a fan or pump or some other external source. Larger amounts of heat transfer are possible utilizing forced convection.

Heat Transfer by Radiation

Radiation refers to the transfer of heat through empty space. This form of heat transfer does not require a material or even air to be between the two objects; radiation heat transfer works inside of and through a vacuum, such as space. Example, the radiation energy from the sun travels through the great distance through the vacuum of space until the transfer of heat warms the Earth.

EXAIR‘s engineered compressed air products are used every day to force air over hot surfaces to cool, as well as dry and/or blow off hot materials. Let us help you to understand and solve your heat transfer situations.

To discuss your application and how an EXAIR Intelligent Compressed Air Product can improve your process, feel free to contact EXAIR, myself, or one of our other Application Engineers. We can help you determine the best solution!

Brian Bergmann
Application Engineer

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The picture “Energy Transfer – Heat” by Siyavula Education is licensed under CC BY 2.0

The Case For The Flat Super Air Nozzles

What do you think of when someone says “air nozzle?” Is it a crimp or a “crush” on the end of a piece of tubing? Is it a device that attaches to the end of a pipe or a hose? If so, does it have engineered features that focus the stream, amplify the flow (through entrainment, perhaps,) reduce the noise level, or provide an element of safety?

If so…you’re right. Any of the above descriptions, strictly speaking, qualify as an “air nozzle,” in fact, just a plain open-ended pipe or tube meets the criteria. As long as it serves to discharge a stream of air towards a target, it’s an air nozzle.

Even the devices with those efficient, quiet, and safe engineered features come in a variety of styles, types, and models. Consider EXAIR’s product line of Air Nozzles and Jets…we have seventy-two distinct models, in a range of sizes, materials of construction, and performance.  That’s a LOT to choose from, and it doesn’t even take into account the products that can be fitted with different shims that, technically, make them a wholly different nozzle, performance-wise.  Which brings us, dear reader, to the focus of today’s blog: the Flat Super Air Nozzle.

Flat nozzles are not unique to EXAIR…there are dozens of others on the market in a variety of sizes and materials.  What IS unique about EXAIR’s Flat Super Air Nozzles is their performance…

Efficiency: When a competitor’s flat nozzle was replaced with a Model 1122 2″ Flat Super Air Nozzle, consumption was reduced from 31 SCFM to 21.8 SCFM.  Since the nozzle was operated 24/7, this resulted in a savings in compressed air cost of $3.31 per day…meaning the nozzle paid for itself in under three weeks.

EXAIR’s Flat Super Air Nozzles have been blowing away the competition since 2003.

Durability: Both our 1″ and 2″ Flat Super Air Nozzles are available in rugged Zinc Aluminum alloy, or heat & corrosion resistant Type 316 Stainless Steel.

Zinc aluminum models are perfect for general purpose blow offs (left,) while 316SS models are specified for food/pharma and high heat or corrosive environments (right.)

Versatility: A 0.015″ thick shim is installed in the Flat Super Air Nozzles.  These provide optimal performance in a wide variety of typical industrial and commercial blow off applications.  We also offer High Power versions, with a 0.025″ thick shim, for additional flow and force.  You can also experiment with other shims, from 0.005″ to 0.030″ in thickness, for customized applications.  These shims are all 316SS, and are available in sets, or individually.  The patented design of these shims, in fact, is key to their high efficiency, as explained in this video:

Ingenuity: While this EXAIR characteristic is not specific to the Flat Super Air Nozzles, our most recent ingenious development features them: the Super Air Scraper.  By combining a scraping blade with the 2″ Flat Super Air Nozzle, we’ve turned our very popular Soft Grip Safety Air Gun into the perfect tool for easy removal of sticky or stubborn debris from most any flat surface.

Scrape off, and blow away, stubborn debris with the Model 1244-48 Soft Grip Super Air Scraper.

EXAIR Flat Super Air Nozzles are Intelligent Compressed Air Products with a 15 year history of successfully solving all kinds of air blowing applications.  To find out more about how they can work for you, give me a call.

Russ Bowman
Application Engineer
EXAIR Corporation
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Accessories and the Value Added

The word “accessory” can come with some baggage… it’s become synonymous with “add-on” and “up-sell,” and cost-mindful consumers may see them as just another way for a slick salesperson to make an extra buck. And frankly, they wouldn’t have that reputation if there wasn’t some truth to it.  The server at your favorite restaurant will offer appetizers, or recommend side dishes to go with your entree. If you go to buy a new car, you’ll get a pitch for a variety of aftermarket add-ons.  The paint counter folks at the hardware store always tell me what specific brush and/or rollers I should use with the paint I’m buying…and it’s never the 10-pack of economy brushes that costs less than the single, premium quality brush they recommend.  In all of these cases, these employees are trained, constantly encouraged, and hopefully rewarded on the success of these “up-sell” strategies.

Of course, my boys and I can devour even the largest plate of chili cheese nachos long before the rest of meal comes out.  My wife absolutely loves the remote starter function that the dealership installed on the new car she bought last year.  And, if you’ve ever painted a well-lit room, you know the difference between a $1 paint brush and a $10 paint brush.  So if my server gets a little bigger tip, my car dealer salesperson gets a little more commission, or the paint counter folks get a bonus, then it’s a win-win, as far as I’m concerned.

EXAIR carries a variety of accessories for our Intelligent Compressed Air Products.  Some aid in mounting & installation:

Clockwise from top: Universal Air Knife Mounting System, Stay Set Hoses, Cabinet Cooler Side Mount Kit, Mounting Brackets for Line Vac, Filter Separator, and Pressure Regulator, Swivel Fitting for Super Air Nozzle, Tool Holder for Industrial Vacuum Drums, Spray Nozzle Mounting Clip.

Others make it easy to ensure adequate supply conditions:

The performance of many EXAIR Intelligent Compressed Air Products can be altered by replacing the shim:

From left to right: Super Air Amplifier, Super Air Knife, 1″ Flat Super Air Nozzle, High Velocity Air Jets, and Air Wipe all feature replaceable shims to modify performance.

In addition to these product-specific accessories, EXAIR carries a complete line of:

Filter Separators are rated for air flow up to 400 SCFM; Oil Removal Filters, up to 310 SCFM.

*Filter Separators to remove water, dirt, and rust from your compressed air system.  Our Automatic Drain Filter Separators have a 5 micron particulate element, and a centrifugal vane to remove moisture.

*Oil Removal Filters with coalescing elements that remove any trace of oil, and also provide additional particulate filtration to 0.03 microns.

 

*Pressure Regulators, so you can “dial in” the performance you need, so you don’t overpower the application, or waste compressed air.  They come in sizes from 1/4 NPT to 1-1/4 NPT, and are rated for flows up to 700 SCFM.  A pressure gauge provides accurate indication of outlet pressure, and the adjustment cap can be removed to prevent tampering.

*Mounting Brackets and Modular Coupling Kits for our Filters and Regulators.  The latter are especially handy for easy, compact, and leak free installation.

*Silencing Mufflers to reduce work area noise from compressed air exhausting from pneumatic cylinders, valves, etc.  There are several styles to choose from, depending on your needs:

  • Sintered Bronze Mufflers are simple in design, with minimal back pressure restriction, and come in sizes from #10-32 thread to 1-1/2 NPT.
  • Straight-Through Mufflers offer noise reduction up to 20 dB, and come in sizes from 1/4 NPT (up to 22 SCFM) to 3/4 NPT (up to 73 SCFM.)
  • Heavy Duty Mufflers have an internal stainless steel screen that not only protects the exhausting components from environmental contamination, but also keeps air system contaminants from being ejected at high speed into the work area.
  • Reclassifying Mufflers are an upgrade to the Sintered Bronze Mufflers and provide the highest level of noise reduction – up to 35 dB.  They also trap oil mist, eliminating breathing hazards to personnel.

*We have manual ball valves (1/4 NPT to 1-1/4 NPT) and Solenoid Valves (120VAC, 240VAC or 24VDC) from 1/4 NPT to 1 NPT, and a Foot Valve, for hands-free operation.

*Swivel Fittings to securely install & aim many of our nozzles, from the Atto to the High Force 1 NPT Super Air Nozzles.  For a little more flexibility, Stay Set Hoses and Magnetic Bases can be used for Air Amplifiers, Super Air Nozzles, and even short Air Knives.

*12 ft Coiled Hoses (1/4″ or 3/8″ ID) and Compressed Air Hose (3/8″ or 1/2″ ID; up to 50ft lengths) can be provided with any Intelligent Compressed Air Product.  We also have a full supply of fittings (tees, elbows, nipples, couplers, reducers, etc.) and adapters to fit our Super Air Nozzles to your existing air guns or blow off devices.

*Receiver Tanks are used to store a ready supply of compressed air.  If you have an intermittent demand of sufficient size, it can cause a pressure transient in your system, which can drag down the ability to supply other points of use.  Installed near the point of intermittent demand, they prevent pressure & volume fluctuations, keeping the operators at all points of use happy.  Model 9500-60 Receiver Tank has a capacity of 60 gallons, is rated to 200psig, and meets ASME pressure vessel code.

In closing, let me offer the following advice that’s served me well over the years:

*Be mindful of the valued added by the accessories & add-ons you’re presented during a purchase of capital equipment…or anything else, really.  Don’t buy something you don’t need, but if you need it…well…it’s OK to buy it.

*Don’t skimp on quality.  Odds are, if an accessory is offered by the manufacturer of the product, it’s going to work well for you.  They should be able to tell you if it will or won’t if you discuss your needs with them.  I know I will if you call me to discuss a compressed air product application.

*Get the big plate of nachos, especially if you’re dining with teenagers.

Russ Bowman
Application Engineer
EXAIR Corporation
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Where Has The VariBlast Compact Safety Air Gun Been All My Life?!?

Have you ever happened across something that would have been a real “game changer” at some time in the past? I’ll never forget the time that I went camping with my sons’ Boy Scout Troop, and I was introduced to the peanut butter and bacon sandwich. I still enjoy one from time to time, but my doctor does not enjoy hearing about it…

I’ve also written before (and before) about when I found out EXAIR Vortex Tubes were being used in some shipyards for freeze sealing pipes…a task that (when I worked in a shipyard) we used tanks of liquid nitrogen for.  I was amazed that such a cumbersome ordeal was replaced by something so simple and easy.

When we were developing the VariBlast Compact Safety Air Gun, a key feature…the variable flow trigger…also would have been real handy at a time in my not-so-distant past.  See, I used to run a small industrial equipment service department, and one time I found myself in a pinch to get a structural steel tube frame made for a support for a particular piece of equipment.  This wasn’t something we did all the time, and this particular job was a bit larger scale than most of what we’d done before.   It wasn’t really a big deal; I just had to cut some rectangular tubing to length with our band saw, drill some small holes (for bolts) and bore some larger holes (for cables & hose) along the length.

We had a small air compressor and a cheap commercial grade air gun, which served the purpose of our infrequent usage. Blowing the shavings away from those holes, and the inside of the tubing was a challenge…that air gun would just barely move them all the way from the holes near the middle, and when I blew out the holes near the ends, the spray of coolant-soaked shavings was making a heck of a mess in our relatively small shop.  After a while, I found that I could kind of “mash” the trigger a little to one side and get a rough measure of control…I was only going to have to mop about half the floor, instead of the whole thing, and I wasn’t going to have to wash the service truck parked in the closest garage bay to the shop area.

Needless to say, this wasn’t exactly ergonomic, and it was  real pain (literally) to use my left hand for a few days following.  Which, being left-handed, was kind of a drag.

Fast forward to just last year, when we rolled out the latest and greatest (in a distinguished line of latest and greatest) EXAIR product: the VariBlast Compact Safety Air Gun.  Now, individually, the key features might not be all that mind-blowing to the casual observer, but taken together, they’re a pretty big deal. Consider:

*Aluminum construction – lightweight, durable, corrosion resistant.

*Two compressed air inlets – one on the bottom (below your pinkie finger) and one on the rear (above your thumb;) your choice…whichever makes your task easier.

*Cast-in hanger – to keep it out of the way, but still handy, when you’re not using it.

*Chip Shield – you still have to wear safety glasses, but this will keep them cleaner.

*Wide selection of engineered nozzles – from our Atto Super Air Nozzle (2.5 SCFM; 2.0 oz force) to the 1″ High Power Flat Super Air Nozzle (17.5 SCFM; 16 oz force,) there are 20 distinct models in stock.  We can customize the performance of the VariBlast Compact Safety Air Gun to the specific needs of your intended use for it.

*Extensions – for applications that require a little (or a little more) reach, we offer the VariBlast Compact Safety Air Gun with rigid aluminum extensions up to 72″ in length.  These are particularly handy when used with the Atto Back Blow Nozzle.

*Variable pull trigger – as the name implies, you can “vary the blast” by how hard (or not) you pull the trigger.  Like I said before, you can do this – kind of – with a run of the mill commercial grade air gun, but it’s not very precise, and far from ergonomic.  Here’s a short video showing just how sensitive that trigger pull is:

If you’d like to give one a try, EXAIR offers these – and any catalog product for that matter  – with a 30 Day Unconditional Guarantee.  We invite you to put it through its paces for up to a month.  If it’s not going to work out for you, for any reason, we’ll arrange return for full credit.  Give me a call – we can talk about how you intend to use it, and which one’s right for you.

Russ Bowman
Application Engineer
EXAIR Corporation
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Small, Precise Blowoff at Your Fingertips

For many blowoff applications, stronger isn’t necessarily better.  For applications and processes where a light, but effective blast of air is needed for cleaning and drying, the VariBlast Compact Safety Air Gun with the Atto, Pico, or Nano nozzle fits the bill. The smallest of the EXAIR engineered Super Air Nozzle family, the Atto, Pico, and Nano have been designed to provide the smallest, most precise blowoff possible. The focused airflow pattern allows for very accurate control and placement of the air stream.  The nozzles are available in both Type 316 Stainless Steel and PEEK plastic (useful for harsh environments, and is non-marring)

img_7480.jpg
The Atto, Pico, and Nano Super Air Nozzles (Scale is in Inches)

The new VariBlast Compact Safety Air Gun is a great choice for putting the power and performance of the nozzle into a small and lightweight air gun. Designed with a variable flow trigger, the airflow can be throttled from a whisper to full force, simply by varying the trigger pull distance.

1698SS
VariBlast Model 1698SS, with Stainless Steel Nano Super Air Nozzle

The Atto, Pico, and Nano nozzles use very little compressed air and are extremely quiet, easily meeting OSHA Standard 29 CFR 1910.95(a) for Noise Exposure.  The design incorporates engineered solutions for safety and can be supplied with higher pressure compressed air and meet OSHA Standard 29 CFR 1910.242(b), relating to dead end pressure requirements.

The table below provides performance data, including the compressed air consumption, force, and sound level for the various configurations.

VariBlast With Small Nozzles

Note that the VariBlast air guns can be had with extensions from 6″ to 72″ and chip shields to meet the performance and safety needs of any application.

The Atto, Pico and Nano Nozzles can also be configured to work with the Soft Grip style of Safety Air Gun.  Consult an Application Engineer for assistance in choosing.

If you have any questions about the Atto, Pico, or Nano nozzles, the VariBlast Compact Safety Air Gun, or any EXAIR compressed air product, feel free to contact EXAIR and myself or one of our Application Engineers can help you determine the best solution.

Brian Bergmann
Application Engineer

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