The CMAXX Inline Deflagration Arrester (IDA) is a proprietary filter design of Imperial Systems. Each collector with IDA filter technology displays a special IDA seal affirming the unit is a certified IDA collector. This certification is in effect as long as replacement collector filters are always Imperial Systems IDA filter elements. Let’s explore the details of our IDA filter technology and its advantages over what other dust collector suppliers offer.
CMAXX as an Inline Deflagration Arrester
It’s important to understand that IDA certification is for CMAXX as a whole system with specific features and configuration. It’s been third-party tested to withstand an explosion of 185 Kst. If a deflagration occurs in the collector, it will completely stop a flame from passing beyond the filter section.
IDA Filters
To begin with, these are not ordinary cartridge filters. We use a proprietary IDA version of our DeltaMAXX Prime filter. It has a second layer of reinforcement that makes it stronger to withstand high Kst explosions. With IDA DeltaMAXX filters in CMAXX, the explosion force will pass through, but the fireball won’t.
The filters will burn eventually if there’s a fire in the dust collector. The filter media itself is flame resistant and with the initial explosion they won’t burn up. If there’s a flame that continues to burn in the collector after the explosion, the filter media may eventually burn away. A standard filter with standard cellulose media would burn up and a fireball would go right through it.
Electric Eye
The IDA package includes a photoelectric sensor. The system installer will put this into the ductwork downstream of the collector. This sensor acts as a broken bag detector to monitor for any compromised IDA filters in normal operation. The sensor will send a signal to a warning device. It may otherwise shut the system down if it detects particulate bypassing the filter section. This is an important feature of the IDA system. That’s because a damaged filter will allow the flame to get through in a deflagration event. If the sensor detects something passing through, the indication is that there’s a problem with a filter. Maintenance personnel will need to replace it.
What Competitors Do
Other manufacturers will offer a second bank of filters. This is to perform the same function as Imperial Systems’ tested and proven IDA filters. There are ramifications of this to consider.
First of all, enlarged collector housings accommodating two sets of filters take up more space. Some companies build another complete filter section on top of their collector to retain the footprint. But this results in a tall collector that decreases headroom for indoor installations. This increased filter housing will also add a considerable amount of extra cost to the collector. However, CMAXX IDA technology does not require this.
Furthermore, secondary filters can prematurely blind since they’re not self-cleaning. This can result in high pressure drop. Plus, there’s an initial extra cost of the larger housing with a second filter set. Further, its replacement costs are more frequent than the primary filters.
No Diverter Valve or Abort Gate Needed
The National Fire Protection Association (NFPA) says that you have to block off all your egress from your collector. So, the ductwork coming into the collector has to have an explosion isolation valve/damper in the ductwork. If the outlet’s clean air is going back into the plant, it must have a diverter valve.
Our CMAXX Inline Deflagration Arrester actually negates the need for that diverter valve or abort gate on the collector’s outlet. That’s because our filters will stop that flame from passing through the filter section.
No Secondary Filter Bank Needed
Our IDA DeltaMAXX filters alone do what competitors do with two sets of filters to stop a flame front. Changes of one set of our primary filters are easy and safe with the patented lift rails in the CMAXX. The safety pentagon built into each CMAXX collector prevents the doors from closing if rails are not locked in the proper upright position, ensuring filter sealing. No secondary filter bank means no added risk of filter bypass allowing a flame to travel through.
Dust and Fume Applications
When can you use, or not use, the CMAXX IDA technology? As we learned earlier, it’s been tested and certified to withstand dust explosions at 185 Kst. So, we need to know or determine what that rating is for your dust and/or fume application.
This infographic identifies Kst values for several dust types. Sugar and cornstarch are highly explosive, yet the CMAXX IDA will stop a flame front from their ignition. Cornstarch was actually used in the deflagration test. Most metals have Kst values much higher than 185, so they’re not good candidates. Just about any dust that’s 185 Kst or below would be an excellent choice.
Installation Location Flexibility
We have customers who have no other option than to locate their dust collectors inside of their plants. With explosive dust, they can place the collectors next to an outside wall so the explosion can vent outside.
Alternatively, they can equip a flameless vent explosion suppressor onto the collector’s explosion vent. Normally, the exhausted air would also need to vent outside. Alternatively, you can equip the collector with a costly chemically suppression system and high-speed isolation gates. But with our IDA, they can keep the collector inside and not worry about venting the air outside. It can discharge right into the plant because there’s no flame that’s going to come by. This opens up many options for CMAXX IDA installation locations.
Summing Up the CMAXX Inline Deflagration Arrester for Fire or Explosion
The CMAXX Inline Deflagration Arrester has been independently tested and proven to meet NFPA standards for stopping a flame front from fire or explosion.
It eliminates the requirement for a diverter valve or abort gate at a collector’s discharge.
It eliminates the need for a secondary bank of filters designed to stop a flame front.
Unlike secondary filters used by others, CMAXX consistently cleans the IDA DeltaMAXX primary filters during operation.
The CMAXX IDA is the best choice for explosive dust with a rating of 185 Kst or lower.
For the Dusty Jobs Podcast Donovan talks with Bob Dayringer an Industrial Hygienist from MyOHSA. Bob talks about what it means to be an Industrial Hygienist and why you should schedule one to visit your company. Also Bob talks about a cautionary tale from a few visits of different companies.
Narrator: Welcome to the Dusty Jobs Podcast from Imperial Systems. Industry knowledge to make your job easier and safer.
Donovan: Hello, and welcome to another episode of the Dusty Jobs Podcast. Thanks for listening again. Today we have joining us Bob Dayringer, retired MyOSHA. Did I say your last name right, Bob?
Bob: Yes. Yup.
Donovan: Alright. So he has been a senior industrial hygienist for, oh man, how many years did you have in the industry Bob?
Bob: Uh, thirty nine and a half years. I was with MyOSHA for thirty nine and half. I was a CIH for thirty some years.
Donovan: Now, what’s a CIH? I’m not familiar with that term.
Bob: A CIH is certified industrial hygienist. It’s the professional way of saying that you know what you’re doing.
Donovan: Gotcha. So those are some initials that give you a little bit of credibility.
Bob: Yeah, the American Board of Industrial Hygiene sponsors a two part test that you take to become certified. It’s a fairly rigorous test.
Donovan: So I’m sure over the time that you were doing that, man, probably the industry changed so much during that time frame. I imagine you saw innovations and regulations and a lot of stuff change, huh?
Bob: Quite a lot of change, yes, over those years. I have said that industrial hygiene isn’t quite as exciting now as it used to be because standards move along. They find out things are worse for you than they originally thought. They lower exposure limits, and when they lower exposure limits, the industry tends to move away from those issues, and the workplace gets a little safer. It’s not quite as exciting when you go into the industries because some of the bad things that were there no longer exist.
Donovan: So it’s not as exciting in a good way. Things are starting to get safer.
Bob: Exciting is now always a good thing.
Donovan: Yeah, so it’s still very interesting and intriguing, but there’s no one probably getting as sick as they used to, or as injured as they used to.
Bob: It makes the days fun when you constantly get the chance to learn new things and to see new things.
Donovan: Yeah, I can imagine. So we kind of talked about what an industrial hygienist is, but we kind of gave a broad definition. What would you say? Would this be something someone would go to college for? How did you actually find your way into it and what does it actually mean from day to day?
Bob: I found my way into it by luck, actually. I was just out of college with a degree in biology and chemistry working as a chemist in a chemical manufacturing facility, and it became my job to escort the MyOSHA guys through the plant when they came to visit us. I saw what they were doing and I thought, ‘Boy, this looks like a lot more fun than what I am doing.’ So I applied and eventually got into MyOSHA. Then there was a big learning curve.
Donovan: Oh, I can imagine, I can imagine. So you started out meeting these guys, and then you said, “I think I’ll do that.” What is a day in a person who is an industrial hygienist? Is it a lot of visiting factories? How does it go about, If I was going to shadow you for the day?
Bob: Most of my days would be going to an industry somewhere. I was in consultation so I went out at the request of the facility. I was able to talk to them beforehand and determine what their concern was. I might do some research about that material or concern, and then go to their facility, do air contaminant or noise monitoring, review ventilation systems to see if they were working as they were supposed to. Those types of things. It’s kind of like being a risk assessment detective. You look for things that can cause risk for the employee.
Donovan: I gotcha, I gotcha. So, I mean, thirty nine years you were doing this. What are some of the most common things you would run into during that time frame? I’m sure it’s changed, like we talked about earlier, but what was some stuff that typically you could walk in and say, “Wow, I see this a lot,” and really help people out with it.
Bob: I would say three things. First of all, noise exposure. Noise is everywhere in the industry. Many, many, many people are overexposed to noise and lose hearing because of that. Number two on the list would be welding fume exposure. I wrote more citations, more hazards, for an air contaminant, for welding fume than anything else by far. Thirdly would be bad ventilation systems, things that were installed to help protect the employee that really didn’t do much or didn’t work correctly.
Donovan: I gotcha, I gotcha. So, there’s something there that’s in place but maybe the design of it or how it was actually functioning wasn’t working to-
Bob: It just wasn’t up to what they intended it to do.
Donovan: I gotcha, I gotcha. Good intentions, bad design possibly.
Bob: Lots of times.
Donovan: So, in all these times do you have any stories about maybe when you ran into something like that where you were just like, “This is not working out at all.”
Bob: One of the ones that really comes to mind is that you have to spend your money wisely. I went into a foundry years ago. My first day there they were so proud. They had just put in this new exhaust ventilation system in the core-making room. I asked, “Why did you put this in?”
They said, “It smells really bad in there so we spent a few hundred thousand dollars trying to get rid of this bad smell.”
Of course, I said, “What is that bad smell? Is it something hazardous? Is it just a bad smell?”
“Well, we don’t really know. It smells bad. People complain, so we spend the money.”
Across the door into the other half of the foundry, it was a leaded brass foundry. Their lead exposure was so high that they had people off on medical leave. It was really hazardous. They had spent hundreds of thousands to get rid of a bad smell and done nothing about the lead.
Donovan: Oh my.
Bob: I always say to spend your money wisely. There’s only so much in that suitcase to spend. They had several employees off on medical leave because of high, elevated blood leads. It was very hazardous.
Donovan: Did you say, “Hey, why don’t we take this pipe that you put here and put it here to help with that lead,” huh?
Bob: Unfortunately it doesn’t work that way. It has to be designed specifically. You should have taken this block of money and spent it in the foundry.
Donovan: They should have had you in there before they started making these decisions, huh?
Bob: I think it would have been a lot better. I certainly would have said, “Don’t do this.”
Donovan: Okay, so lets say there is a setting – you talked a lot about weld exposure – in this setting it was lead exposure. How would a person even know that? How would they go about getting a test or figuring that out? How do you guys do that? How do you let someone know when their exposure limit is too much or if they’re within it? What’s the process in helping people determine that?
Bob: If it’s noise, we have digital readout, equipment that takes the noise sample constantly thorough-out the day. It provides us with an exposure number at the end of the day. If we’re doing air contaminant monitoring then we usually have an air sampling pump and we’ll pull air through some type of media that collects the contaminant. We then send it to a laboratory and they do the analysis, and we can say that for that period of time, this is how much material was in the breathing zone of the employee. For instance, for welding fume we take that sample right inside the helmet. We put a cassette inside the helmet and we suck air through that cassette and then have the cassette analyzed.
Donovan: Wow. So you can’t get any closer to that unless you were going to put it in their nose.
Bob: Exactly, yes. We want it to be in the breathing zone. The definition of the breathing zone is within six inches of your air intake.
Donovan: So if you’re talking about weld fume exposure, when you would typically see someone that was inside or outside that range, what does that range look like? How does that measure?
Bob: The range of welding fume exposure?
Donovan: Yeah. So, if someone was welding for ten minutes or welding all day – if I was a welder and I was looking at this how would I know if I am exposed too much or if I’m within the acceptable limit?
Bob: Most everyone now is a MIG welder. Most of your welding in the industry is MIG, metal inert gas. It’s a wire fed system. I would say rule of thumb if your production welding and you’re welding more than three hours a day, and you don’t have some sort of ventilation system to collect that fume you’re probably going to be exposed above the Michigan exposure limit. Exposure limits are different depending upon where you’re located.
This gets to be a long story, but Michigan’s exposure limit is five milligrams of contaminate per cubic meter there. The feds – Federal OSHA – states still ten. It really needs to come down from there, from either place. A couple years ago IARC, the International Association for the Research of Cancer, has now called welding fume a carcinogen. So, there’s that. There’s manganese in all of welding fume. The manganese exposure limit for the feds was five. It’s going to – well, ACGIH, American Conference of Governmental Industrial Hygienist, is recommending that it be limited to 0.02.
Donovan: Wow. So, things are getting even less exciting, right? Hopefully.
Bob: Hopefully they will get less exciting, right? Right now if you’re a welder you’re overexposed to manganese and probably welding fume in some states if you weld more than three hours a day.
Donovan: So the functionality and having a good system in place to get that weld fume away from that operator – we’re becoming more and more aware of how important that is for people’s health and safety.
Bob: We’re recognizing now the importance of getting away the welding operators, definitely.
Donovan: So if someones out there and they have a weld shop and they’re thinking, ‘Man, I would love to have someone like Bob to come in and look at my operation and tell me where I could make things better or help.’ How would someone do that? Is it a paid service? Is it a government service? From what you used to do, how would someone get in touch with their dental – or not dental hygienist! What am I saying here – with their industrial hygienist that is in their area?
Bob: If they’re in a state plan state, if their OSHA program is ran by the state, all of the state plan states have consultants that come in free of charge. In federal states, I’m not aware. I think some of them also have consultation programs. The first thing I would do is check the web and see if my state had that availability for free service. If not, there is a variety of paid consultants that will come out. There are many organizations that have IH’s working for them that can come out and do this monitoring.
Donovan: I know some people would say, “Why would I want to call OSHA into my facility?” That’s just a scary thing to do. But, from what I remember talking about earlier kind of what you guys did and what the other side of OSHA does is a little bit separate. Is that right? The consulting side in comparison to…
Bob: Compliance and consultation are totally separate. Compliance does not know where consultation goes or what they do. As a consultant, we are requested by the employer to come in. We provide a report to the employer that gives them some direction of what they need to do to come into compliance. It’s a free voluntary chance to come into compliance with standards. There is a catch. Consultation does request a gentleman’s agreement that they will fix what’s broken. If we find something seriously wrong, they need to fix it, or we’re required at some point in time to turn it over to compliance. It very seldom happens because typically the people that have consultation come in that know that up front and are willing to fix what’s broken.
Donovan: They’re coming to you saying, “We know there is an issue. We’re trying to find a solution.” That’s such good information. You guys out there with OSHA are really trying to help make the workplace a safer, cleaner environment, a healthier environment. Here at Imperial that’s what we try to do too. We’re a little bit on the other side of it, just continuing to build equipment. So it’s a really great to hear that out there in the field what we’re doing can really help somebody go home safer to their family at night. That’s what we’re shooting for here.
Bob: Everyone laughs at that statement. “I’m from the government. I’m here to help you.” In this case it’s really true.
Donovan: Well, Bob, do you have anything else that might be helpful for anyone out there if they’re listening and thinking, ‘Man, I don’t know if I have any exposure to anything.”
Bob: I think it’s never a bad idea to have your consultant come in and review your data sheets and review your operations and see if there are things that might be of interest to look deeper into. Again, over time yo kind of get a feel for what can be a problem. With that length of service comes some knowledge that makes it easier to tell what might be an issue.
Donovan: Yeah, yup. Well Bob, thanks again for coming on. We really appreciate it. Maybe we’ll do something again in the future. We could cover some other topics. We really appreciate your wealth of knowledge and being willing to share it with us.
Bob: You’re certainly welcome.
Donovan: Everyone who is listening out there, if you’d like to reach out to us more you can find us Twitter, Instagram, Facebook, LinkedIn and now we have a Tik Tok! So you can watch us on Tik Tok. Once again, thanks for listening. Everybody out there stay healthy and stay safe.
Bob: Thanks Donovan.
Donovan: Thanks Bob.
Narrator: Thanks for listening to the Dusty Jobs Podcast. Breathe better, work safer.
Magnesium metal is used in manufacturing across a wide range of industries. It can be found in items that we rely on every day such as car seats, laptops, cameras, and power tools that benefit from being lightweight. According to Research and Markets, the market for metal magnesium is expected to grow at a compound annual growth rate of more than 4% globally by 2026. What this says is that magnesium metal is here to stay, so it’s important to know how to both safely handle magnesium while working with it and how to properly dispose of it and its waste after. This is where dust collection comes into play.
Hazards of Magnesium Metal Dust
Magnesium is an excellent conductor in heat and easily ignites, therefore it must not only be handled with care – it must also be cleaned up with care. While solid magnesium metal may be difficult to ignite, finely ground magnesium dust is “ready ignitable” and can even spontaneously ignite in the presence of water or cutting fluids containing fatty acids. Machining or sawing magnesium can create this airborne dust and grinding residue that can hang in the air and settle throughout the workplace.
Given that it will burn and explode with violence if ignited, it’s imperative that non-sparking conductive tools be used where magnesium metal dust is present. Any smoking, open flames or electrical welding must also be forbidden in places where magnesium is machined, sawed, or ground.
Why Proper Dust Collection is Important
If left to collect on workspaces and equipment, a magnesium metal dust explosion is waiting to happen. Sparks from any source can ignite the substance and the resulting fire can quickly travel. To make matters worse, there is typically more than one explosion as the initial explosion often shakes more accumulated dust that in turn ignites. OSHA says that these later explosions can be far more devastating due to the increased quantity and concentration of dispersed combustible dust.
The danger of having magnesium dust in the workplace is severe, so its handling should be treated as such. According to the International Magnesium Association, grinding dust should be captured in a wet dust collector system that is engineered for magnesium and dedicated to magnesium use only.
Avoid a Dust Explosion with Proper Magnesium Metal Dust Control
Exposure to dust and gasses in factories can be hazardous to workers’ health. Furthermore, flammable dust produces an environment conducive to a fire or explosion. This is especially true for magnesium metal, whose use in manufacturing is expected to rise in the coming years. When working with magnesium metal, make sure that you’re keeping a safe and compliant workspace by monitoring dust collection. It is the only way to ensure the health and safety of everyone when working with a metal that produces a highly flammable, easily ignitable dust by-product.
Consult the Dust Collection Professionals
Make sure the company that constructs and installs your dust collecting system is familiar with and can explain all of the required fire safety equipment to you. Another crucial safety tip is to ensure that the equipment is in good operating order via ongoing monitoring. This involves changing the filters as needed and inspecting and maintaining the collector on a regular basis.
Imperial Systems will work will your business and application to advise you on the safest option for your magnesium dust. We can help you determine what will make your system NFPA compliant, whether it’s our heavy-duty CMAXX Dust & Fume Collector for dry dust or pointing you in the right direction for a wet collection alternative.
If you would like a hands-on education in dust collector maintenance, our ServiceMAXX team can pay a visit and help you establish a maintenance schedule.
Charlie Miller meets us for another Campfire Chat. This time Charlie talks about his years in the industry and some of the nasty dirty jobs he has had quote on and measure. Some of those jobs goes back to his days of living in Cincinnati and visiting meat packing plants or going to a waste treatment plant. Check out this podcast to hear more about these dirty jobs.
Intro: Welcome to the Dusty Jobs Podcast from Imperial Systems. Industry knowledge to make your job easier and safer.
Donovan: Hello, and welcome to another episode of the Dusty Jobs Podcast. Today we have a very special edition with Charlie Miller. Charlie has been a long time employee of Imperial Systems, and used to write for our newsletter, the Dusty Jobs Newsletter, with an article called ‘Good Luck With That’. Charlie’s article reflects on his time in the industry with fun stories. Now we’re going to move that into the podcast realm. Charlie is now going to be doing Campfire Chats. We hope you enjoy these stories from Charlie Miller. Thanks for joining us.
Charlie:
Hi everyone, welcome back to Camp Imperial.
Pull your camp chair up next to the fire,grab a hot dog to roast, and sit a spell for another campfire chat.
Anyone a Mike Rowe fan? He had a TV show called Dirty Jobs. On each episode he would take us to some of the nastiest jobs you can imagine .
Who begins life saying the want to be a garbage collector or city sewage worker when they grow up? These are nasty jobs, and somebody had to do them. But sometimes these undesirable jobs can be very profitable. Let’s face it , dust collection is all about cleaning up in dirty places and over the years I have visited some nasty places.
I spent a large part of my career in Cincinnati, Ohio. Many people don’t know this but at one time in the early years Cincinnati was known as “Porkopolis”. One of Cincinnati’s earliest enterprises was a meat packing center. The Pig Farmers would drive their hogs right through the center of town to the stock yards. Legend has it that Cincinnati is where the phrase “When Pigs Fly” originated. Truth is the folks in Cincinnati are proud of their Porkopolis heritage and play tribute to the Flying Pigs that helped to make them a major metropolis area. If you look hard enough, you can find tributes to flying pigs everywhere in Cincinnati. (Watch out, there goes one now! They’re cute little fellows but you got to be careful about their droppings)
The stock yards are still there, and meat packing is still one of the major businesses in Cincinnati. I once had to visit one. They wanted a stainless-steel hood and exhaust system installed over a large meat fryer. The fryer was in a room that had about 50 gutted hogs hanging from overhead conveyor hooks. The pigs were split open but still had their head and feet. I had to maneuver around these dead pigs to get my measurements done. Not only a nasty job but creepy as well. I’m glad they gave me the white coat and hat to wear. I couldn’t wait to get out of that room. I did get the order though. My customer asked me to come back on Wednesday. I asked why and he told me Wednesdaywas slaughter day. I declined the offer.
Speaking of meat packers have you ever wondered how they make skinless wieners. I was called into another meat packer who made them. The wieners start out as a bunch or finely ground up pinkish-gray mystery meat to which is added a bunch of nitrates and preservatives. (EUW! Throw away hotdog)This pinkish meat mush is then injected into a continuous sleeve that is twisted every 4 of 5 inches to form the wiener. This continuous string of wieners then goes through a cooker that solidifies the wiener into the form we see in the store. After exiting the cooker, the sleeve is slit longitudinally allowing the wieners to separate and fall out sending them to packaging, while the slit sleeve, still dripping with juices from the cooking process, is sent to waste.
That was why I was there. The wet sleeve went through a chopper and then sent outside to a cyclone receiver over a compactor. The cyclone was wearing out and had to be replaced. Since there was no information on the cyclone, I once again had to field measure it. It was the middle of Julyand the discarded sleeve material that was already collected in the compactor had turned rancid in the summer heat. It also attracted a bunch if bees that were swarming around the cyclone I had to measure. It just goes to show that our food suppliers can have nasty jobs too.
Have you ever wondered where all the roadkill animals you see along the highways go to? After they are picked up by the highway department, many of them are sent to a rendering plant, commonly known as the glue factory. While glue is one of the byproducts from rendered animals, many other common productsbegin with organically rendered materials including : pet foods, lubricants, soap, shampoo, paint, elastomers and even explosives. Did you know gelatin deserts are made from rendered animal bones?While rendered organics are recycled into many useful products, visiting one of these facilities is not a pleasant experience. Along with dead animals, many other organics materials are rendered including rancid cooking grease collected from restaurants that are thrown into a big vat for processing. The odor is horrendous. One visit is enough to ask for a pay raise .
Coming in a close second to rendering plants are chicken processing plants.Have you ever driven by one in the summer? It makes you think twice about dining at the colonel’s house.
Another place with similar attributes is the good old Metropolitan Sewage Plant. This is the place where all the toilets flush to. Can you imagine what it is like to do work there?The MSD was one of my regular clients and I affectionately referred to them as “The Turd Grinder”. One memorable job I was involved with was to make and install stainless steel drip pans under the miles of overhead process pipes running throughout the sewage plant. Understandably the sewage workers did not want any of that stuff leaking on them should a pipe joint spring a leak. It was a nasty place to visit but I’ve been told some funny tales from the workers. You would be surprised at some of the things people flush down their toilets. And the people who work here have seen it all.
Chemical plants have their own nasty characteristics to cope with. A large petrochemical plant along the banks of the Ohio River has miles of large stainless-steel duct that runs throughout its various production buildings. This duct system is about 20 feet above ground level so traffic can drive beneath, and it is used to transfers waste to a centralized filter. They call it their “Sewer in the Sky”.Periodically sections of the duct would corrode from the materials being conveyedand need to be replaced. This usually required specialized clothing and respirator masks to be worn when replacing the duct. In mid-summer working from elevated man lifts in the hot protective gear is not much fun.
Another chemical company I did some work for made AcetysalicylicAcid, which is better known as Aspirin. They had one multi-story building with a large enclosure in thecenter where the acid was condensed into a usable form. Over time condensed residue would build up and solidify on the inside of the enclosure wall panels causing themto deform. The ductwork would also clog with the same material which required both the panels and duct to be periodic replaced. Every few years I would go into that building to field measure the panels and duct that needed replaced. Aspirin is a beneficial pain and fever reducer. But in the condensation process a fume is generated which caused my eyes to water and burn within minutes. I would often need to leave the area just to clear my eyes of tears. It amazed me that people could work in that building every day.
Chemical companies are not the only places that will cause your eyes to water. Going into some food processing plants will cause the same problem. I once visited a spice plant that was making hot sauce. They had a 1500-gallon vat where they cooked the hot peppers and other ingredients to make the sauce. The top of the vat was covered with a canopy hood and ducted to a roof mounted exhaust fan that disbursed the cooking fume up into the atmosphere. They called me because they needed a replacement exhaust fan and had no idea what volume or horsepower they needed. To determine this, I had to visit the plant to examine the fan. The stairway up to the roof was in the same room that housed the cooking vat. By the time I reached the top of the stairs, tears were streaming from my eyes. After inspecting the fan name plate, I was able to determine the volume and horsepower requirements for the replacement. The fan was badly corroded, and I assumed it to be very old, but I could tell it had a stainless-steel housing. I told them I could get them a stainless-steel replacement fan but they told me I needed to supply something better than stainless steel. The fan I was replacing was less than two years old. That was some serious hot sauce!
I had a similar experience at a mustard company where horse radish sauce was one of their products. In the horse radish room several workers sorted the roots by hand andfed them into a washing process. From there they were fed into a machine that finely grated the root to be made into the sauce. Tubs of ground horse radish was stacked in carts around the room awaiting the next stage of production. My eyes watered immediately upon entering the room. Except for a single wall mounted panel fan this room had no ventilation at all. Little wonder the workers were crying for one.
Perhaps the dirtiest places I’ve visited are coal generation power plant. These plants are full of conveyor belts shuffling coal from one transfer tower to another and creating a coal dust nightmare. Even with a well-designed dust collection system it is all but impossible not to come out of a transfer tower without having black coal duct on your clothes. I once visited a power plant with a co-worker to see what we would need to do to install a dust collector on the top of a coal transfer tower. We knew we would need a large crane to set the equipment. The tower was nearly 80 feet tall. There was a rigging company nearby, so we decided to stop in after we left the power plant to see if they could help. Before we left, we used the compressed air hose provided to blow the coal dust off our clothes. Satisfied with our cleaning efforts we drove over to the rigging company. We entered the building and crossed the lobby to the receptionist desk. Shegreeted uscoldly and told us no one was currently in the office who could help us. We wondered what we did to offend her.When we turned to leave, we saw two tracks of black footprints across the lobby carpet leading right up to where we stood. Who puts light beige carpet in the lobby of a building anyway?
I’m rarely required to visit nasty places anymore but it you think I miss it, well good luck with that!
Thanks for visiting and come back again soon for another campfire chat.
Donovan: Thanks for joining us today. We hope you enjoyed this time listening to Charlie’s stories. If you’re interested in hearing more of them, you can go read Charlie’s article ‘Good Luck With That’ on our website. If you’re interested in more podcasts or more information, you can follow us on YouTube, Facebook, Instagram, LinkedIn, and most other social media platforms. Thanks for listening. Stay healthy, and stay safe.
Outro: Thanks for listening to the Dusty Jobs Podcast. Breathe better, work safer.
As with most industrial manufacturing processes, metalworking generates dust that you must deal with. But metal dust can have unique properties which make it especially dangerous. Metal fires in dust collectors are not unusual and can certainly explode. Let’s discuss why metal fires start as well as what you can and must do for fire safety in metalworking environments. Then we’ll cover what to do (and not do) in a real metal fire emergency.
Flammable Metals in the Workplace
Fires with burning metal are categorized as Class D fires. To begin with, all of the alkaline metals in their solid state will burn easily, even spontaneously combust at low temperatures. Some examples are sodium, lithium, rubidium, and potassium. Then there are a few other metals like titanium and magnesium which in solid form ignite only under extreme heat. But once ignited, they can quickly and easily spread into a very dangerous and destructive fire.
The most common industrially used metals in Class D metal fires are aluminum, magnesium, and titanium. Therefore, these metals in dust form are extremely hazardous in dust collection systems. However, most metals in a fine dust form can ignite and produce dangerous situations in confined dust collector systems. The finer the dust, the more likely it is to burn.
Common Metal Fire Causes
Most Class D metal fires occur from processes that create metal dust like cutting, drilling, and grinding. These can produce metal dust fine enough for combustion. As mentioned, a common metal used in manufacturing is aluminum. In its solid form, or even as larger chips created by manufacturing processes, aluminum can remain inert. But finer aluminum dust can be highly explosive when exposed to oxygen and an ignition source.
Metal dust collection should never be mixed with other materials or dissimilar metals. For example, metal dust should never be combined with a wood dust application. A simple spark can easily ignite wood dust, causing a potentially dangerous metal dust explosion.
Aluminum dust should never be combined with a ferrous metal dust system. Machining of ferrous metals can create sparks resulting in a metal dust explosion. Ferrous metal dust (iron) can quickly oxidize. It will create sufficient heat to spontaneously combust. Aluminum dust can also react with water to form highly flammable and explosive hydrogen gas.
Fire Safety Starting Point
When setting up a metalworking operation in your plant, you’ll need an evaluation assessment. Make the first call to your insurance company as they want to make sure that the plant is safe. They usually require that a third party come to your facility to perform an evaluation. The National Fire Protection Association (NFPA) now requires a risk analysis.
They’ll identify the minimum requirements and develop a plan to meet them. In their report, they’ll tell you what issues to address and what steps to take to resolve them. This will include everything from equipment requirements to employee safety training.
Dust Collection System Design for Fire Safety
There are important considerations in selecting and configuring a dust collector for a metalworking application to ensure fire safety. But before we can start looking at any equipment or options, we need to collect some data.
Dust Sample Analysis
The dust collector supplier needs a good, representative sample of what will go through the dust collector. That’s for analysis to determine how flammable it is and what the Kst value is. The higher the Kst, the more explosive it is. Metal dust types with high Kst values are very volatile and very dangerous. With this report and information about the challenges of the application from the customer, the dust collection system design can begin.
AHJ Collaboration
AHJ stands for authority having jurisdiction. You will need an AHJ to approve the dust collection system you’re submitting for installation. The NFPA defines an AHJ as an organization, office, or individual responsible for enforcing the requirements of a code or standard, or for approving equipment, materials, an installation, or a procedure. This could be a fire chief, your insurance company, somebody with the NFPA, or someone else. Again, call your insurance company first.
The AHJ will review the dust collection system that you intend to install for the application. They’ll tell you if anything needs to change in order for it to be approved. In addition to the dust collector, there may be other requirements they’ll bring up like special fire extinguishers.
Fire and Explosion Protection Components
The AHJ may require installing a dry chemical system to extinguish a fire inside the dust collector. A chemical system recognizes a rise in temperature or a rise in pressure. It has fast-acting dampers on the inlet and outlet that isolate the fire. Then it immediately floods the collector with a chemical suppressive that smothers the flames. The chemical system contains the fire and keeps the dust collector from exploding. It does this by taking the oxygen away and absorbing the heat. The collector cannot have a typical water system in it. Water can cause further reaction to metal dust. It can act as an accelerant and add more fuel to the fire.
If the dust collector doesn’t have a chemical system and has explosion vents, the vents will blow out with a ball of flames. It’s going to burn the collector and potentially anything nearby. Therefore, isolation is the best thing you can do for a metal fire. Imperial offers another, NFPA conforming option to isolate a deflagration and stop a flame front. It’s the CMAXX with the proprietary IDA (In-Line Deflagration Arrester) DeltaMAXX filters. There are other combustible dust and fire accessory components as well. Spark traps, explosion-tested drum kits, and flameless explosion vents are a few.
Best Prevention Practices for Metal Fire Safety
Here are ways you can avoid metal fires in your plant. So far we’ve discussed potential fires inside your dust collector because that’s where you’re most likely to have one. But metal fires are also possible in metal processing areas throughout a facility. You should develop safety procedures and follow them when performing any manufacturing process on metals (cutting, grinding, drilling, etc.).
Segregate the Metals
All combustible metals should be separated and stored in secure locations or containers. This is especially important for metals that combust at low temperatures. More so, it’s critical with highly reactive metals like sodium, which burns on contact with air or water.
Metal dust should never be combined with anything else in the dust collection system. Earlier we talked about the hazards of collecting metal and wood dust together. If you have aluminum machining, that’s all you should be pulling into the collector. Nothing else should be going in there. Do not combine metal dust with anything else. Even aluminum and steel should not be mixed.
Yes, that means a separate, dedicated dust collector for one type of metal dust. This is a hard truth to hear because naturally, you don’t want to pay for two systems. Even aluminum chips will catch fire down at a certain size. The finer metal dust gets, the more it’s susceptible to burning.
Keep Up Good Housekeeping
Clean up work areas and do not allow metal dust to accumulate on any surfaces. That includes the floors. If you’re running a machining process that’s creating dust, it’s going to build up. That includes the rafters. This is especially important because you typically don’t see the dust piles up there.
The danger is in the accumulation, which can be the source of a secondary fire or explosion, ignited by the first one. Good housekeeping practices should be routinely performed.
Periodic Fire Safety Evaluations
This is the very best way to prevent a fire from happening. Have a qualified company come into your plant and perform a full risk assessment at regular intervals. They’ll advise you of any problem areas that you need to address. This is an NFPA code requirement of every commercial manufacturing property. Its purpose is to identify and eradicate potential fire hazards in the workplace. Insurance companies usually enforce these periodic evaluations.
Dealing with a Metal Fire Emergency
Despite your diligence and prep work to prevent a metal fire, it’s still always possible that you may have one. An ember or spark can find its way onto a flammable metal dust pile if good housekeeping isn’t maintained. It could also find its way into the dust collector if a spark trap isn’t installed. You would be surprised how easily an ignition source can inadvertently occur at an inlet suction point. Besides obvious employee evacuation, what should you do in the event of an actual metal fire at your plant?
Use Extinguishers Specifically for Metal Fires
We learned earlier that metal fires are classified as Class D fires. These are extremely dangerous because most people do not know how to properly fight them. Typically, the first thing people want to do is throw water on a fire or use a regular extinguisher. However, that’s the worst thing you can do for a metal fire. It just fuels the flames. If there’s a pile of metal dust on the ground that’s burning, water is not going to put it out. It’s just going to wash that flame into different areas of the plant.
So, you really need a dry chemical type extinguisher that is specifically designed for Class D fires. This smothers the fire and the oxygen fueling it. It also absorbs heat within the fire, leading to its extinguishment and reducing the chance of the fire spreading to other areas. Have Class D-rated extinguishers ready for use and train your employees on when and how to use them.
Leave a Burning Dust Collector Alone
More than likely, if you have a metal fire it will start in your dust collector. You or your employees may be tempted to try and extinguish it. Stay away from it. Here’s why.
If the collector has a chemical suppression system installed on it, that will isolate and extinguish the fire as explained earlier. This is the best scenario. Let the chemical system do its job. Do not open the doors to try and extinguish the fire yourself or check it afterward. We know now that oxygen will fuel any metal dust flames, so don’t open the doors. Leave it alone and call the fire department.
We’ve already discussed a collector that does not have a chemical suppression system but does have common explosion venting. The temperature and pressure will build up, eventually blowing out the vents. A ball of flames will be released. With properly sized explosion venting the collector likely won’t burst apart from the explosion, but it will continue to burn. In any case, you don’t want to be near it when that happens. Leave it alone and call the fire department.
The worst-case scenario is if your collector doesn’t have a chemical suppression system or explosion venting. It’s going to explode and burst apart from the rise in heat and pressure. Essentially, it is a bomb. Don’t approach it or try to relieve the growing pressure by opening the doors. Leave it alone. Evacuate according to plan. Call the fire department.
Keep Fire Safety a Priority
Avoiding metal dust fires has special challenges. Determining the danger potential of your specific metalworking application takes effort. So does cooperation and compliance with authorities. It’s a tough decision to buy an additional, dedicated dust collector just for metal dust. After all, dust collectors don’t contribute to your production output. Plus, over time it’s easy to become neglectful of good housekeeping, recurring safety training, and periodic inspections. Decide to keep your employees safe and your plant running with proper preparation and procedures for metal fire safety.
Imperial Systems, Inc., a manufacturer of industrial dust and fume collectors, has recently opened a new office location in The Colony, Texas. This expansion will allow Imperial Systems to better serve the vast array of manufacturing companies thriving in Texas. “We hope we can continue to grow our footprint in the South-Central area of the United States.Having this office will also better position us to work with our local partners, contractors, and dealers of dust collection equipment in that area,” said Justin Ferrainola, the South-Central Territory Manager at the new Texas branch.
Imperial Systems has already had the pleasure of working with many companies in metal, wood, and other industrial industries in the Texas region.With the new branch office, we will be better positioned to expand our focus into the many other markets throughout the territory.
The Colony is situated in the ideal location for the growth that Imperial Systems has in mind. “It is close to Frisco and McKinney, which in the greater Dallas area, has seen the most rapid growth in manufacturing” said Ferrainola. The Colony is only 30 minutes from downtown Dallas, and 40 minutes from Fort Worth. Beyond that, Oklahoma City, Austin, Houston, and San Antonio are all within a five-hour drive.
Hazards of Magnesium Metal Dust
Dust Collection System Design for Fire Safety
Use Extinguishers Specifically for Metal Fires
Imperial Systems, Inc., a manufacturer of industrial dust and fume collectors, has recently opened a new office location in The Colony, Texas. This expansion will allow Imperial Systems to better serve the vast array of manufacturing companies thriving in Texas. “We hope we can continue to grow our footprint in the South-Central area of the United States.