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Machine Guarding

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 hazards.

For this series we are at the beautiful Monterey Bay Aquarium to show you that no matter where you work, safety is for everyone.

Recently I was at a large manufacturing facility and the safety team there asked me if I could help them learn how to do hazard assessments for machine guarding. And what I shared with them is what I've put into practice in the 20 years that I've been in this field and over 500 places of employment that I've been to and how to really assess machine guarding.

So today where we are at the Monterey Bay Aquarium on cannery row but that aquarium actually used to be a cannery and behind me is an old piece of equipment and it's a box printer and it put labels on boxes. And so this is actually kind of a perfect piece of equipment to try to break down what the hazards are with machine guarding. And so when I do an assessment or a breakdown I'm looking for things and looking for the point of operation, I'm looking for rotating parts, I'm looking for in running nip points, and I'm looking for things that create flying chips or sparks and we have three out of those four on this particular piece of equipment.

And so let's walk through that and then we'll look at a few other machine guarding examples in the aquarium so on this box printer where we have the point of operation is where the work is actually happening. And so with this the boxes were fed through these rollers and the rollers would apply a label so that's where the point of operation is, meaning the employee is standing there feeding materials into the area which could get them caught into or in this point rolled into the point of operation. And so that would be a place where we would look for a hazard and there would be a hazard here and then we look for guarding. And when it comes to guarding the other rule that I apply is if there's a guard on something or if there isn't could you reach over, around, under, or through to the point of operation. And with this since there aren't any guards right here which if maybe was in the way back. We would have access to that point of operation where someone could get hurt and pulled into this machine. And so then if we move just up here a little bit we have what could be an in running nip point depending on how this machine operated.

When you're doing your hazard assessment with your safety team you're looking for things that are rolling and if they're rolling inward and can pull a person in or their clothing in or their hair in then we have a hazard there that would need machine guarding. And moving along we'd be looking for more moving parts.

When this machine was operational a long time ago there would have been a belt over these pulleys and this would have all been rotating and without a guard in place this would be something that you could get caught in to these spokes as it's moving. And so this would be an area that would need guarding and then we move a little farther and we have these chain and sprocket drives and more of them over here and again we'd watch the equipment as its operating and see if they're moving inward that could pull someone in then that would be a hazard that you'd want guarded. And in this area anytime we have any kind of chain drives we can get people caught in this. Now this has a partial guard on it and so you'd apply that question. Can I reach over around under or through to the hazard? And in this case we could so this guarding would be inadequate for today's standard. And so that's the those are the points that we want to look for with machine guarding so remember we're looking for hazards where we have point of operation in running nip points rotating parts flying chips and sparks and then once you identify those risk areas then ask yourself: How can I guard this in a way or is it guarded adequately enough so that I can't reach over around under or through? So next let's take a does take  look at some other places in the aquarium at some machine guarding examples. So now we're going to talk about the hazard of flying chips and spark something that we didn't see on the on the labeling machine a little bit ago.

So we're standing in front of a metalworking lathe and again we have a point of operation and the point of operation on the metalworking lathes is right in this area where the cutting is going to be happening and so when that's occurring and this is spinning. It's creating chips and those chips are little pieces of metal. Depending on the size of the stock they can be much larger and they can be hot and very sharp and as this is working those chips are going to be flying in different directions including at the operator and they could cut the operator or they could be hot and land on their skin and burn them. And so when we're talking about a machine guarding method for flying chips or sparks which is what this is producing we have what's called a chip shield. We would bring this chip shield in place over the point of operation and then the employee would be wearing safety glasses like I'm wearing now and put on a face shield additionally and long sleeves to protect them so their skin if the flying chips were to land lets say on their arms so that they didn't get burned or cut.

And so we've talked now about points of operation guarding and in running nip points and rotating parts. And now we're seeing an example of a piece of equipment that produces flying chips or sparks and those are all things that we want to be mindful of as we're doing our hazard assessments and looking for different places where we need to apply machine. Here we have a motor and pump and when you're doing your safety audits some of the things you want to look for in areas like this are rotating shafts, and what we have here is a rotating shaft that's under this guard right here and this  guard happens to be a really nice design and kind of a newer design. Often times you will see shaft guarding that would include this entire area and what we're trying to protect from of course are those rotating parts like we've been talking about.

This particular guard is really nice and tight and nearer the rotating part and it also has a little area where you can actually adjust the guard to the length of the shaft that's exposed which is really a great asset to be able to have. So again when you're doing your safety audits you're looking for rotating parts you're gonna find them on unwish on motors like this with pumps and then look for your guard and make sure that the entire shaft itself is protecting people.

Before we end our session here on machine guarding I wanted to point out one more guard, it's a very nice extended expanded metal guard that is protecting a belt drive system that's it that's a great kind of guard and a tip what I'm using expanded metal that I've learned over the years is if you paint them flat black they're often a lot easier to see through. If the operators need to make adjustments or do inspections on them.

Now something else that I've picked up that I'd like to share with you that I've learned over the years of doing machine guarding assessments is when you're doing your audits try to be looking for things that look like tools that maybe employees made for themselves. Sometimes maybe it's a long shaft or maybe something that's got a curved hook at the end or something that has duct tape on it or maybe a wooden stick of some type and ask the operators in those areas what those things are for. Sometimes employees have issues with machines where they're trying to maybe bypass a guard or something is broken or there's a particular jam in an area where they might be putting themselves at risk and so be on the lookout for tools that have been homemade by employees who are trying to do good work and trying to get their jobs done every day but they're finding ways to make that happen by modifying what they're doing. And as a safety professional or a supervisor you want to be on the lookout for those things so you can improve conditions for employees.

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.