Peace Between Machine Safety, Productivity

Friday, September 27, 2013 @ 04:09 PM gHale


By Ellen Fussell Policastro
“There’s a conflict between safety and productivity – sometimes referred to as war,” Pat Barry said.

Barry, the regional marketing lead for safety at Rockwell Automation, described ways to achieve a safe and productive environment with machinery in a Rockwell/ISSSource webcast last Wednesday. Click here to download an on demand version of the webcast.

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But the conflict doesn’t have to occur. There is a place where safety and productivity can coexist with each other. Sometimes safety can even enhance productivity if you do it the right way.

“We live by two rules to keep people safe. The first rule is, if you need access to a machine, you turn it off. Second, if a machine is running you keep away from it,” Barry said. The term Lockout/Tagout (LOTO) refers to isolation of energy and machine guarding. But when we resort to LOTO, “we end up with a well-guarded machine that nobody can work with while it’s operating,” Barry said. That of course is not practical, so we need to revisit how to run machinery safely and be as productive as possible at the same time.

Active vs. Passive
LOTO, an active safe guard, lets you perform maintenance tasks, “but we also have this medium space known as a minor service exception that says for certain tasks we are allowed to use something other than LOTO and allow someone to access a machine without going through the formal LOTO process,” he said.

So if we have to access the machine, we have two choices: LOTO or an alternate means of hazardous energy control. LOTO is an active safe guard. That means an employee has to take action to implement that safeguard. When we use alternative means, we design the safeguard so it’s passive. That means an employee doesn’t have to do anything to take advantage of that safeguard. It’s kind of like the seat belt versus the air bag in an automobile, Barry said. “With a seat belt, somebody has to take action to implement that safeguard. In an airbag system, they are protected by that safeguard just by driving; they don’t have to do anything extra.” This is the same principal we want to apply when talking about safeguarding people around machinery.

Safety Can Enhance Productivity
The first goal of machine safety system is to keep people safe naturally, and it has always been about that. But this has led to a perception that safety equals LOTO. People think safety means stop. That perception has continued despite advances in standards and technology.

If you believe safety means stop, that would lead to the safest companies being the least productive. “But we have data that shows the opposite is true. The companies with the best operational performance also have the best safety performance,” Barry said. “So that perception is something we continually have to fight against.”

How do these companies implement safety so they can stay productive? They design safety at the start of the recipes, thinking about how humans interact with machines, and they streamline that process. Then they do a true risk assessment. They evaluate risks with hazards and choose safeguards to match that level of risk.

One important concept is the hazard control hierarchy. “If you have to reach in and clear a jam, first you have to figure out why there’s a jam and then try to get rid of it,” Barry said. “When you think of it that way, you’re not just going through a safeguard exercise but a productivity exercise. But you start from the aspect of safety.”

So how does this process lead to productivity improvements?

• Design tasks out of the process. If there’s a jam, and we can eliminate the source, the machine stays up longer.
• Make improvements through industrial automation. Give the system some intelligence and make it react to situations better than in the past. This gives more information to operators and allows them to resolve problems faster.
• Implement alternative methods of control. If we do have to get into the machine, we design a system that allows someone to perform a task using safeguarding systems.

Good Risk Assessment
How do we use a good sound safeguarding process to find improvements? The standards all say the same thing and describe a safe guarding project through design and installation, Barry said. Then over time you can monitor and make sure the system doesn’t change. But one common mistake is to place safeguards without considering how it will affect people trying to do their jobs. This ends up hurting productivity.

Before you step into a good safeguarding process, make a decision about how to prioritize your machines, he said. Don’t skip steps; go through the prioritizing activity.

To decide which machines to attack first, look at which ones have had incidents or near misses. Which ones are oldest or being replaced? It’s much less important how you decide than it is to just have a methodology to make that decision, he said. So go through the prioritization exercise first.

Then you can move into the detailed process. The first step is a risk assessment. One example is a slicer, Barry said. The task is to clean the cutting section three times per day. The hazard is the potential to cut or sever something due to an unexpected start. The current safeguard is LOTO. Pick a standard for your assessment. That will help you rate the risk in a consistent fashion and measure the level of risk that a person encounters as he or she goes through that task.

Here’s where the user can decide which safeguard he’ll put into place, Barry said. “Can I design the hazard out? What about a guard, monitoring process, or interlocked gates? If we can do nothing to the machine to protect this person, then we look at protective equipment. It’s all about coming up with options. What if we use an alternate method? We’ll put a locking guard. Here’s where standards can help.”

If you’re using an alternate method, make sure you’re designing this safeguard according to the level of risk, Barry said. Pick a standard and go with it. But watch out for red flags — minor service exceptions for certain tasks. We can use alternative energy methods and design circuits to address that level of risk. We need to control the circuit that powers the motor, not the one that tells the motor to stop and go.

The slicer example is an actual incidence in which someone moved from LOTO to an alternate measure — an interlocking guard that removed energy when it was open and resolved the problem, he said. Rockwell met the standards for safety and reduced the duration of shutdown. “We allowed the user to increase their daily production by 17 percent. That’s a significant difference in their productivity,” he said. “Again, it was the result of using a good safety process and understanding how people will interact with machinery.”

Invest in Technology
While generating the best operational and safety performance involves use of good risk management strategy, robust procedures to figure out risks, and standards, it is also based on a good safety culture and a company’s willingness to invest in new safety technology.

But remember a good safety program is a progression, not an event. You don’t sign up to use contemporary safety technologies and just have them work. It doesn’t happen instantaneously, but it doesn’t have to take years to generate. Buy-in has to come from the top and cascade down through the rest of the company, and it has to be enforced. It can’t be without reward or without consequence.

“One of the places we see a common thread is where people have LOTO processes, they have to make sure they enforce the policies in place,” Barry said. “Also make sure you involve people working on machines, and make sure they’re rewarded for their involvement. Nobody knows a machine better than those people working on it.” If you get their buy-in, you go a long way helping them do their jobs safely and efficiently.

Click here to view Barry’s presentation.



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