Machine Safeguarding
Episode 6
November 3, 2020
Rob Hamm:
Welcome to another get sparked episode. I’m your host, Rob Hamm, along with Dave Larson. And we’ve got a special guest today, Mike Plesnarski. Welcome on the show, Mike.
Mike Plesnarski:
Hi guys, thanks for having me.
Rob Hamm:
Mike, you’ve worked at R-V industries for eight years now, and prior to that, you owned your own company called AccuDraft. Could you tell us a little bit about your experience with AccuDraft, and how you got started at R-V?
Mike Plesnarski:
Sure, AccuDraft was started by my father actually back in 1978. And then in 1996, I acquired the company from my father and kept it in the family and ran it for 16 years. During that time, we worked with a lot of different industrial clients. Our niche was machine design equipment designed for a variety of industrial companies. So I got to see and work and learn about a lot of different processes and equipment during that time. In 2012, one of my longtime customers has been R-V Industries and they acquired AQI draft, and I became the Engineering Services Market Manager.
Rob Hamm:
Thanks for sharing that Mike. I never knew AccuDraft was a company you inherited from your father. That’s great to hear. Today we’re going to be talking about machine safeguarding. So Mike, would you be able to share with us a little bit about your background and how you got involved in machine safeguarding?
Mike Plesnarski:
Machine safeguarding has become probably the most important area among all of our industrial customers. One thing they all have in common is we all want to protect our greatest asset, which is our people. And we want to make sure that they all come home to their family the same way they came to work. So that being said in the industrial environment, each company has similarities in the way they handle their machine safeguarding and some have differences and some have nothing at all. So getting the opportunity to work with all the various customers across the different industries, I learned a lot of best practices. You know, one company does really well with this and another one does really well with this and I try to put it all together and come up with the best, most safe solution in our design work.
Rob Hamm:
So it seems like a lot of you were background, a lot of your experience from working with all these different companies and working with RV industries has gained you a lot of experience in that. What are some of the first steps you take when a customer comes to you and says, can you help us with safeguarding? What’s that process look like?
Mike Plesnarski:
There’s different ways to go about it, depending on if it’s a new piece of equipment that you’re designing for them, or if it’s an existing piece of equipment. So the first step is to obviously select a process line or a piece of equipment that you would like to safeguard. So that could come from a continuous improvement effort on the company to always continually try to improve safety, or unfortunately, a lot of times it’s started by an injury and that prompts corrective action to be done. I found some interesting facts on osha.gov website where every year they average 18,000 amputations lacerations, crushing injuries, abrasions, and over 800 deaths per year. In 2019 there were 1,743 cited violations for machine safeguarding. Interesting thing is OSHA only has 2100 inspectors and we have 130 million workers in the country. So when you look at the numbers there and break it down, it’s one compliance officer for every 59,000 workers. So the 1,743 violations in 2019 with those numbers being considered, it would be reasonable to say there are many, many, many more violations out there that have not been discovered.
Rob Hamm:
It sounds like a lot of that’s going to come back down to, with a company wanting to proactively implement safeguarding and protecting for their employees. I guess some companies don’t even realize they have a problem.
Mike Plesnarski:
A lot of companies don’t realize they have a problem. The majority of the companies we work with really do put safety first and they are proactive with trying to prevent injuries. But let’s face it. A lot of these big manufacturing and industrial firms have been around since the turn of the century. And a lot of them have very old equipment from back at a time when safeguarding not real prevalent or wasn’t a priority. It was a lot more dangerous to work back then than it is now. So it’s a huge undertaking. So even though a lot of these companies are trying to constantly improve their safeguarding. They can’t get to everything at one time and it’s something that’s going to take many years. So one of our first steps is a risk assessment and that starts with identifying a hazard. So if you pick a certain process line and maybe you selected that process line because of your history of accidents, maybe there’s a pattern of injuries on this specific line and it needs to be addressed. So the first step is to identify the line that you want to safeguard and then identify the hazards. You always do that by committee. So the next thing is to assemble your team for safeguarding. It’s not something that one person should do by themselves. So what does that team look like? Well, you should have someone from engineering. Obviously who’s going to design the guarding and the solution, a person from safety from the company’s EHS department. Oftentimes these people are certified safety professionals and can provide you a lot of really good insight from a safety perspective. Next, you should have an operator. The person who’s working on that line. He understands all of the tasks that he has to do. And finally maintenance because safeguarding is not just to protect the production worker. It’s also to protect anybody who may be working on the machine, which includes maintenance. From time to time, they have to perform work, and we need to make sure that they’re safe. Assembling that team is very important and that’s for several reasons. One big reason is that whatever guard, whatever safeguarding method you choose, it can not pose more of a hazard than what you’re trying to protect. That’s why it’s important to get feedback from our production side to say, Hey, if I, if I guard this in this way, is this going to make your job any harder? Because you don’t want to put them in positions or prevent them from doing their job that may make them take more of a risk. And you’ll find a lot of operators, if a guard is hard to work with, they will find ways to bypass it. Getting buy-in from an operator is very important because then they also feel part of the solution and you’ve created something that they can easily work with. And the same goes with, with maintenance, you have maintenance there. They need to access the machine to change out parts, to troubleshoot it. And they’re oftentimes bypassing the guarding through a lockout tagout program, which is something that’s very, very important to consider when you’re doing machine safeguarding, that the machine is properly shut down and all stored and hazardous energy is dissipated from the machine. The maintenance person can let you know what tasks he has to perform, so you know how to create the logic behind your safeguarding methods to allow him to do his job as well.
Dave Larson:
Mike you mentioned a little bit about building the team that’s going to look at safeguarding initiatives. How did you go about the somewhat difficult discussion about the benefit of safeguard and protecting from serious injuries and even the fatality numbers that you mentioned, it’s a tricky conversation to have? How did those conversations go?
Mike Plesnarski:
Two things, one starting from a corporate level or the business decision makers that want to spend capital money to improve safety. A lot of times they’re coming to us and asking us for a solution because they have that culture of people first and they care about their employees first and foremost. Second thing, any employee at any time can make a phone call to OSHA if they feel something is not safe in their workplace. And that would prompt OSHA to come in and do an investigation and could, uh, give you a citation for it. And the employee is completely anonymous throughout this effort. So most of our customers don’t want that type of culture where employees feel unsafe doing their job. So safety’s always very much welcome. From an operator perspective, that’s the key with including them in your team. When you include them in your team, and they know that their input is valued because it sincerely is. You cannot create an effective safeguarding plan without input from the operator and they feel part of the team and they feel part of the solution. They’re more apt to not have a negative reaction to the guarding.
Dave Larson:
Hmm. Yeah. That makes sense. If the is going to work around to anyway, unsafely, it’s not going to be an effective safeguard, right?
Mike Plesnarski:
I have seen instances where people in engineering just recognize the hazard and said I’m going to throw a guard up here without ever taking into consideration what the employee has to do. Does he have to access that area routinely? Have you just caused him a lot of extra steps? And then they, you know, start to feel like their input is not valued because they’re wondering why didn’t someone ask me before they put this up. We could have done this instead. So it’s very important on the front end, prior to starting the risk assessment, that you put your team together and go through the risk assessment process as a team.
Dave Larson:
Absolutely. Thanks for jumping into that a little.
Rob Hamm:
Mike, what’s the most difficult part about determining the right guard to use.
Mike Plesnarski:
The most difficult part is going through the risk assessment, because there are so many options of guards that can be used, but each one has to be appropriate for the functionality of the machine or, or the steps the operator has to perform there. As part of the risk assessment process. You walk the line together as a team, you, recognize hazards and you list those hazards. We use a risk assessment form, which is, an Excel type format based on ANSI B 11 T R3. And what that does is we can list all of the hazards for the machine. It’s a description of what it is. And then we categorize the severity of it. You know, how severe of an injury could someone get? Would it be basic first aid? Would it be serious injury? Would it be death? You know, that’s one of the metrics we use. The next metric is what’s the likelihood of avoiding the hazard. It’s either likely or unlikely. And then the next is the frequency of exposure. How often would somebody be exposed to this hazard? You take those three metrics and it comes out with a risk level of low, medium or high. That allows you, when you want to prioritize your corrective actions. You want to put all of those high risk items first, and then you come up with a plan to mitigate that risk. So we’ve identified all of our high risks. So now you go through a process step with the operators where they let us know every step they have to take around that machine, and we determine what’s the best guard. Would it be a fixed guard? Can it be there all the time and would never need to be removed? Or do you need access into this general area where we may have to use sensing devices such as light curtains? So that would be one of the most challenging parts is getting through that risk assessment process as a team and coming up with the best solutions that are good for everyone all around.
Rob Hamm:
We use the term safe guarding when people talk about it. In my mind, I think some large shroud, you know, guarding your hand from a spinning object. There’s lots of types of safeguards, Right?
Mike Plesnarski:
There are, in the safeguarding process, some of the guards we typically work with is one fixed guarding. That’s a lot cheaper to implement. You know, it’s generally 80 20 material with expanded metal or any type of metal frame, but it’s fixed to the machine and protects the worker from like an in-feed nip point or something that he never has to access, but could have incidental contact. Maybe the only time he would reach in there, which is the leading cause of amputations is jams trying to clear jams. So operators reach in there to try to push something through that may have gotten stuck and they ended up getting injured. So fixed guarding prevents that from happening. Some general guidelines with fixed to guarding is it should always require some type of special tool to remove. In other words, you don’t want it to just hang there on a bracket where an operator can take it on and off as he pleases. You always run the risk that the operator could forget to put it back on or just not use it at all. So your, fixed guarding is considered more permanent with needing a tool to remove. We have movable guards also, which we do a lot of work in the metals industry where they have coil to coil process lines. So there’s a lot of ingoing nip points between pinch rolls and things like that, which is hard to guard, especially on their winding and unwinding sections of the line, because the role of metal or material it gets smaller or bigger. And the location of we call it the past line of the material leaving. It has a range of motion up and down to compensate for the full or empty spools. So we would put some type of movable guard that could, either ride along with the metal and let the metal move it up and down with it, or use some type of other electrical device to move the guard along with the material.
Mike Plesnarski:
Another thing is perimeter guarding. When it’s just not practical to guard a certain process and people need to access it. We put perimeter guarding up, and oftentimes, well, all the time that perimeter guarding should be interlocked. The area will not let you in until the machine shuts down, or when you open the perimeter guarding, that will cause the machine to shut down. And you should also have provisions to make sure nobody’s, if you close the door, the machine thinks it’s safe, but you have to make sure nobody’s inside also. So there are challenges with perimeter guarding that you have to work through. That’s where another presence sensing device could come in, in combination with the perimeter guarding, where you have a laser scanner or some type of camera that can detect if somebody’s inside the perimeter so that if someone would inadvertently close the perimeter guarding door, it would not allow somebody to, initiate the machine. A lot of times we’re using combinations of guarding to all work together.
Dave Larson:
Do you find that to be pretty frequent in terms of combining multiple types of safeguards?
Mike Plesnarski:
Yes. Yes. Normally there’s always some type of interlocking feature or electrical component to safeguarding. It’s very rare to be able to have fixed guarding, take care of everything. You don’t want to have fixed guarding and have an operator require a tool to open it. If it’s something that he has to use all the time. If he has to access it all the time to feed material or to do a setup or whatever, if he has to get a special tool and it has to work to take it off, he’s just going to leave it off. Then you have to have some kind of guard that is maybe, uh, a hinged door that’s innerlocked so that the operator cannot access that until the machine is de-energized. We are always finding ourselves using a combination type guard of some sort.
Dave Larson:
And that’s where the importance of a diversified team of corporate level and operators and maintenance personnel is really important. That’s where it comes into play in reality, right?
Mike Plesnarski:
Yes. That’s very important. You will never understand the machine as well as an operator or maintenance individual does. Especially if you’re like us who are consultants and, we don’t work in the department as an engineer with the company to get years of experience with watching the operator operate the machine. We’re oftentimes going into a facility and seeing a process for the first time. We start with observing the operator, actually working the machine and understanding the limits of the machine and what all is involved with it. Asking a lot of questions to the operator upfront asking him how he does this, how he does that. Is there anything he feels unsafe doing. So that initial understanding and input from the operator and maintenance personnel is vital. I can’t stress that enough.
Rob Hamm:
Mike, do you have any kind of formula or guidelines that you use when determining which type of safeguard you’re going to use, whether it’s going to be a perimeter sensor, or when it’s going to be a combination, is there sort of a formula that gets you to the end to make those decisions?
Mike Plesnarski:
You always have to follow at a minimum OSHA 29 CFR, 19.10 sub-part 0. That is a very general guideline. They are the ones that can come in and cite you for violations. So at a very minimum, you have to follow OSHA guidelines for guards. I recommend the ANSI B 11 series ANSI goes above and beyond is more detailed than OSHA. If you’re following ANSI, you’re more than covered for the OSHA requirements. What I like about the ANSI standards is the B 11 series goes through specific types of machines and gives you guarding requirements and recommendations for these machines. But they also have ANSI B 11.1.9, Which is in that series, but it covers general machine safeguarding, which applies to all the machines and interpreting it is, is much better with ANSI because their standard, if you purchase it and look at it on the left, they will tell you what the standard is.
Mike Plesnarski:
And on the right side of the sheet, they have an explanation column where they explain the standard. So it’s much easier to follow. So when you’re doing things guarding, you know, one of the general rules, if is if you’re going to guard something, you cannot reach over it under it, around it, or through it. OSHA has standards that you can go by if you’re doing perimeter guarding. For instance, you can’t have a four-foot high perimeter guard and have the hazard one foot away. Because even though you have a perimeter guard, you can still reach your hand over and get the hazard. So they have formulas and tables, which you’ll also find in our machine safeguarding handbook, that we put on LinkedIn, the height of the perimeter guard and the distance away from the hazard and the height of the hazard. Those three dimensions work together so that you can properly guard yourself from it.
Mike Plesnarski:
Another guideline would be for presence, sensing devices that may stop the machine. Take a light curtain for instance. Light curtain is something you set up that forms up a light barrier in front of the hazard. That’s designed that when you break the beam with a part of your body, it shuts the machine down. So one formula is very important when implementing those types of safeguards is the stop distance formula. And what that basically is, is if you have a hazard and you break the beam of the light curtain, and if that hazard slowly coast to a stop, you can reach it before it completely stops. And then the light curtain really did not do you any favor? So it’s a function of your hand speed. They have a constant for the normal person, the average person’s hand speed, the stopping time of the machines that requires you to shut it down and time it, how long does it take to stop? And then that tells you your distance away for your light curtain or your safe guard. Other things for guard openings, they have size of openings for guards based on the distance, away from the hazard. And all of those things can be found in ANSI B 11.1.9, or OSHA 1910. And those are basically the guidelines that everybody should be familiar with at a minimum.
Rob Hamm:
Those are good. Leave it to engineers to have a formula for everything.
Mike Plesnarski:
This is true. This is true
Rob Hamm:
Hand speed formulas.
Dave Larson:
And it helps make sense of the world, right? Mike,
Mike Plesnarski:
It does help make sense of the world. It explains a lot.
Dave Larson:
Mike, you mentioned a couple of different times about OSHA citations, you know, for, for certain safeguard and violations. What did those look like? Is there a wide range? What do companies have to consider? Not only the people, but also the OSHA rules and regulations.
Mike Plesnarski:
Machine guarding is just one Subpart of ocean. They can come in and cite you for a lot of things outside of machine safeguarding, machine safeguarding is in their top 10 every year, most cited violations. You also have to consider fall protection, confined space, the machine safeguarding as, as part of an overall plant safety is a small portion. There’s a lot more to consider. So when you’re doing a risk assessment or designing a new piece of equipment and going through a process hazard assessment, which is very similar, where you list all the tasks that have to be performed from startup to shut down on the machine. We always consider a lockout tagout. So when maintenance has to work on the machine, they need to be able to de-energize the machine and they need to be able to put a lock to prevent somebody from powering it up.
Mike Plesnarski:
That’s they’re locked out. So they have safe access to the machine. Things that need to be considered is when you have hydraulic systems and pneumatic systems, you have accumulators as part of those systems, which store your hydraulic fluid under pressure, right? It’s, it’s very similar to a capacitor and an electrical circuit. It’s storing energy. So you can shut the machine down. And that energy will stored in there, which could cause a sudden hazardous motion and hurt somebody. So when you go through the process of designing machinery or upgrading machinery or making existing machinery safe, you should always look at the hydraulic and pneumatic systems and ensure that they have an automatic dump valve, which means you need to have power on to keep it pressurized. And if you lose power or power shut off, the valve opens and all of your hazardous energy or fluid can drain back to tank or drain out through a vent.
Mike Plesnarski:
And then the other is ergonomics. That’s another part of plant safety. Monitoring the weights of the objects the operators have to interact with. Is there anything that’s sharp? Is there anything that’s hot. Try to keep anything they’re lifting at 40 pounds or less, hopefully much less. And if they do have to push, pull or lift, always make sure that you’re allowing them to do that in their power zone, where they’re not getting into an awkward position where they could stress their back and cause an acute injury or one that develops over time from repeatedly being in bad posture. Considering lockout tagout. Considering ergonomics. Fall protection. Make sure if you recognize areas, maintenance needs to be at a height that you have areas for them to tie off. So that’s why you do that as a team and the importance of having a E.H.N.S. person available safety engineer. A lot of times they are certified safety professionals, and they’re trained to look at additional hazards that you may not think of when you’re focused on machine safeguarding and that you can address together as a team.
Rob Hamm:
Mike, I was just thinking you don’t just do machine safeguarding. You help design and engineer entire machines from food and beverage industry to baking ovens down to, metal winders. When you’re designing these machines. I guess you’re keeping all of this in mind, not just safeguarding, but you’re keeping ergonomics in mind, safety the employee, as you’re designing machines as a whole, right?
Mike Plesnarski:
Absolutely. Yeah. So as we design machines, we go through the process hazard assessment procedure and recognize hazards. And when you’re in the design phase, you have the unique opportunity to design a hazard out. That should be your first goal. Is can we design this differently to eliminate the hazard altogether rather than to minimize the risk to it? So that process has to be considered on the front end and performed as a team, just as a risk assessment would when you’re trying to provide for an existing piece of equipment.
Rob Hamm:
As well as the operation and function of the equipment itself to do the job.
Mike Plesnarski:
Correct. You engage your mechanical engineers, your electrical controls people at this point, and they’re responsible for designing the safety circuits and the E-Stops and making sure they’re following NSPA 79, which provides safeguards for fire and electrical hazard.
Dave Larson:
What are some of the common myths about equipment safeguarding in terms of just things that are maybe too over the top or not doing enough? What are some misconceptions that you see in your conversations with people at the corporate level, but also operators?
Mike Plesnarski:
One of the biggest myths or one of the misconceptions companies can make is assuming that new machinery you buy will meet safety standards. Don’t make that assumption. When you order a new machine from a manufacturer, every company who’s going to be utilizing that machine should do their own risk assessment and make sure it is compliant and safe for your work. Don’t ever assume that you buy a machine from any company that it’s going to come in compliant. That just exposes your operator to risks and is good on the front end. So R-V Industries, as a manufacturer of custom equipment, we engage our customers on the front end to ensure that all of our equipment comes out safe and is compliant with safety standards. Not all companies are like that. So when you get a piece of equipment and always do your own risk assessment on it. Another misconception would be the fact that guards only protect the workers.
Mike Plesnarski:
Sure. The operator is the one that is around the machine the most and needs protection and takes a lot of the focus. But you also as mentioned earlier, have to consider the maintenance personnel who will be fixing and working on the machine. And finally, just people walking by who would happen to be in the area. You know, you always see people touring a facility for the first time with somebody and they’re walking through the aisle or looking at a process and they’re learning about it. And being able to keep them safe is really important. So you have to consider that as well. And I guess finally, the belief that because you have a more experienced worker, who’s worked on the machine all the time, that you don’t have to worry about providing safeguarding. A lot of times, when you have someone who’s been working around and on a machine for years, yes, they understand the hazards of the machine they’re working with, but the same time they lose their fear of the machine. They become desensitized to and a lot more confident. So they may be the ones that are more prone to taking the risk of clearing jams or accessing areas that they shouldn’t be because they’re just very comfortable around the machine. As opposed to someone who’s starting for the first time and is a bit terrified of it. You know, not knowing what to touch, what it’s going to do. They’re very, very cautious. So machine safeguarding should not ever be based on the experience of your work or working on the line.
Rob Hamm:
Mike, there’s a, some excellent points. As we wrap this up, would you share with us, one of your favorite pieces of equipment that you worked on or had the opportunity to work on since you’ve well, not just here at RV, but just your career in general?
Mike Plesnarski:
Oh boy. When I think of one I know probably after, after this podcast, I’ll think of another one I like better. I’ve done, done so many and have enjoyed so many of them. I would say one that comes to mind right now is a safeguard we did. That was actually part of a process that was really neat. This was more of, of a laboratory type environment. It was outside of manufacturing. A big laboratory asked us to design a custom machine for them, where they put some type of chemical in these flasks and they would put them in these vibratory shakers and then take them over to another process to empty them out. And they wanted one machine that would do all of those steps automatically for them. So, so we designed a machine where they could put eight glass flasks onto a rotating shaft, but the safety element of that was we had a tempered glass front that came down. And as soon as they loaded the machine, they would initiate start and nothing would move until that glass shield came down and then it would start rotating. So the glass shield, if a stopper came out and it splashed the glass shield protected the operator from that, from the splashing, if a piece of glassware would come loose, it would hit the glass sash and not fly across the room and hit somebody. So it had a very important safety aspect to it. But the process end of it is what was happening to them before. Is this chemical after it was done, spinning or being agitated required a minimum of a seven minute dwell time before it could be transferred. And a lot of the chemists there would not monitor that so close and say, yeah, it’s close enough to seven minutes. Or how long has it been or taken too soon? So we programmed that glass sash, which did not allow access. We programmed that to have a seven wait time after the machine stopped to open and allow access. So, so that not only provided safety for the workers, but also improve their process as well. And I really enjoyed working on that.
Rob Hamm:
Actually sounds like you integrated multiple safeguards in that as well as sensing movable, inner locked in that instance.
Mike Plesnarski:
Yes. It was a lot of programming utilizing safety PLC and, that’s the importance of doing the process hazard assessment upfront. So you can match safety with process. You know, one of the items that came up was okay, what’s the next process step? Glassware has to dwell for seven minutes before being moved. So then you logically ask yourself, well, how can we make that happen? What’s going to prevent an operator from just removing the glass from the holder. Oh, we can combine a functionality with the guard that is on a timer that when the machine stops it, won’t lift up and give them access for seven minutes. That’s a great feature to have upfront, you know, and we could have only done that by working as a team and gathering all of those requirements.
Rob Hamm:
Mike, thanks so much. Actually I think this piece of equipment would really help me out in my kitchen between the splash guarding and the keeping the glass from flying across the room.
Mike Plesnarski:
You may need some type of fire protection to Rob from what I understand.
Rob Hamm:
Seriously, Mike, thanks so much for your time. Thank you guys for having me. I enjoyed it. Get Sparked is a series of podcasts, focused around all things, manufacturing. Join us next time. As we get sparked about innovations in manufacturing.
