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Combustible Dust

Hi, I'm Jill, chief safety officer with Vivid Learning Systems. I'm a former OSHA inspector, and I'm here to help you identify and correct workplace safety hazards. For this series, we're at Southern Minnesota Beet Sugar Cooperative in the heart of the upper Midwest, to show you, no matter where you work, safety is for everyone.

When many of us think of combustible dust, we might think of grain dust and grain elevator explosions, especially here in the upper Midwest. The fact is, there are many more combustible dust, not just grain dust. There are a wide variety of dust in many industries that can be explosive. Combustible dust could be from plastics, or wood, or paper, or pulp, rubber, pesticides, even pharmaceutical, dyes, coals, or metals like aluminum, chromium, iron, magnesium or zinc. And even in the food industry it could be sugar, spice, starch, flour, or feed dust.

And today I'm with Brandy, safety director here at the Beet Sugar Cooperative. And Brandy, you do have some combustible dust here at the plant. How many do you have, and what are they?

We have four combustible dust, and we teach our employees about them, not only during orientation, but again annually, to remind them of the dangers of combustible dust and how to protect against an explosion. So, we have four, although you see many samples here. This is part of how we try and hands on and engage with our employees. The four that we have are pallet dust, coal dust, sugar dust, and sulfur pellet dust.

And so, you said you do some hands on training?

Yes.

Yeah, tell us about that, because it sounds like some unique training you've been doing with your employees.

Yeah. We've been having a lot of fun, actually. I try to trick them, and make a little bit of camaraderie out of it. But I basically asked my employees, "Which one of these jars contains a combustible dust?" And they ask me, "Well, which one? What is it?" And I say, "Well, you don't get to have a label out in the factory, so I want you to be able to recognize these materials in the areas that you work." And so they kind of look at them a little bit differently.

Yeah. They're not labeled when they're suspended in the air.

Right, right. But you know, it's a little bit easier if it is in the plant, because they understand the process and what might be in the area. So, they go through a conversation amongst their peers, and they segregate out what they think, and we talk about each one of these dust and the hazards related to each of them, whether it's combustibility, or maybe it's an irritant. And that's it. We walk through all the different hazards associated with the dust on site, but highlight those that are considered combustible.

Sure. And so, how are they eliminating, when you're teaching them and they're picking them up and looking at them, what are you teaching them to look for?

Well, one of the key factors of a combustible dust explosion is suspension. And so, when I hand them this product, which I don't know if you guys can see it, but there's ...

It's not doing much.

It doesn't really get into the air, and it's definitely too moist for that, and that's a conversation to have. But sometimes you pick up one like this, which is a coal dust sample, shake it up and you can see clearly that it's very easily suspended, the finer the material. We have the conversation about the granularity, or how fine the material is, because really, the finer the material, the higher the potential of it getting suspended.

Right. And so, after you kind of teach them those things and they're picking up and shaking, and they're learning, "Oh, so this is what combustible might mean." So they're figuring out the qualities.

Absolutely. And the area has to be ripe for an explosion, meaning you have to have a fuel source, a dust. You have to have oxygen. You have to have an ignition point. Furthermore, for a combustible dust explosion, you also have to have containment of some sort. And of course, the suspension of the material.

Right. And so, after they learn what a combustible dust is in their work environment, and some ideas to identify, to keep themselves safe, what sort of techniques, maybe housekeeping things ... what sort of things do put in place to prevent an explosion of a combustible dust?

Yeah, we have a lot of things that we do to manage this potential hazard, and the biggest thing is minimize the dust from being created at all. So, we do a few things from an engineering standpoint. We have bearing monitoring, so that takes care of an ignition source potential and getting ahead of it beforehand. Another engineered solution might be ventilation, where you're pulling it out of the system, getting it into a bag house and managing it.

So there's opportunity for it to be in the air.

Correct. Correct. Which alludes to that housekeeping comment as well. But we also have things, God forbid you do have a spark or a problem in one of these areas where dust is, we have explosion suppression systems that are automatic. So, you have some preventative things, you have some response things, all commingled. At least in our industry, history shows that it's not necessarily the first combustible dust explosion that hurts people or the process, but it's the perpetuation that occurs. So if we can suppress it immediately, the ...

Th next one and the next one.

Yes, don't happen.

It won't keep happening.

Right. So, from an engineering standpoint, those are a couple things. We might even slow down our bucket elevators, so that the dust isn't even created. Those are the type of things from an engineering solution. From an administrative kind of component, we have permits, we have programs, we have training. And then again, the next step of making sure that we're doing our housekeeping program, that we're doing our inspections, that we're doing our preventative maintenance correctly. All of those things really do lead into a much safer workplace.

And so, the housekeeping measures that you're doing would also be things that would be non-sparking equipment and using that kind of ...

Yeah. We do employ intrinsically safe tools in these areas, whether that be a vacuum system that is completely grounded, and again, intrinsically safe. We have cameras and radios that are intrinsically safe.

And lights.

Lights. Absolutely. And of course, we do have the non-sparking tools, which some people don't know how to recognize what they are, but they're traditionally more of a gold or copper tone material, versus a metal hammer that has more of that aluminum or silver color to it.

That could cause a spark.

Yeah.

Right. Makes Sense. Thank you so much for sharing this, and your unique method.

Thank you.

Yeah, great. If you're concerned about combustible dust in your workplace, or are wondering where to start learning what is combustible or is not, you could start by contacting one of your insurance carriers and ask them for help from their industrial hygienist or the safety professional. Workers' Compensation carriers and property and liability carriers usually employ safety and health professionals to help their insured, and it's a service you're already probably paying for, You just may not know that you can ask for it.

I hope you gained a safety skill today. If you know someone who needs this, go ahead and pass it on. Safety is everyone's business.