Lean Manufacturing: Unexpected Benefits for Accident Prevention

Along with improved efficiency and productivity, lean manufacturing offers companies a path to improved safety. Safety managers need to know how to promote this powerful philosophy in their operations.

Safety has been getting an unexpected boost at some facilities that, in the past, did not seem so committed to a proactive safety approach. Old school employers are unexpectedly adopting many of the processes, terminology and tactics of the safety profession.

It's not driven by a sudden safety epiphany, but just the same, it's happening. In spite of the absence of useful help from our federal government, these facilities have found new tactics to compete with the unfair monetary policies and substandard wages of China, and assaults by other Third World competitors. Lean Manufacturing, a phrase that wraps up many modern philosophies in one term, has become important at these facilities. Improved efficiency, productivity, profitability and, yes, accident prevention are the results. Safety professionals need to be aware of the cultural shift towards Lean, the resulting opportunities, and how to exploit their possible roles in the future.

Eliminate the Waste

In case you haven't heard of it, Lean means more than pinching pennies (some of my clients say, "We have been working lean for 70 years!".... Whoa, wait a minute, there's a substantial difference!). In Lean, the goal is to eliminate anything not essential to the process. The goal of Lean Manufacturing is to eliminate the seven wastes of Lean overproduction, unnecessary motion, inventory, waiting, transportation, defects, underutilized people and extra unnecessary processing.

Cutting these wastes becomes an over-riding philosophy in Lean operations. In practice, this means a cultural shift towards reducing the seven wastes using a 5-step thought process proposed by James Womack and Dan Jones in their 1996 book, Lean Thinking, to guide managers through a lean transformation. The steps are:

1. Specify value from the standpoint of the end customer.

2. Identify all the steps in the value stream.

3. Make the value-creating steps flow toward the customer.

4. Let customers pull value from the next upstream activity.

5. Pursue perfection.

The goal is to find better ways to do the most productive work with the least expenditure of time and materials, with slim inventories and overhead. The desire is for flexibility and reliability, to economize on staffing and to keep rejects low.

Everything that adds value to the process stays; everything that does not add value is waste and should be eliminated. But Lean isn't mean. People who are removed from non-value-adding activities should be given other jobs in the organization. These people often go to the Lean Improvement office or to work that is in-sourced from suppliers into the floor space freed by Lean. Over time, attrition will reduce headcount as the lean transformation improves productivity. Unfortunately, many companies don't launch a lean transformation until they are sinking. Management should cut immediately to the right level of people and promise that no one else will lose a job due to the introduction of lean techniques.

Steps in the Process

Identifying the work elements in a process is the first step. Then the work elements are identified as to those that add value and those that do not. The process then undergoes a refining phase that is essentially continuous, although the major benefits will probably materialize quickly, with diminishing returns as time goes on.

Value Stream Mapping is the creation of a simple paper-and-pencil diagram of every step involved in the material and information flows needed to bring a product from order to delivery. A current-state map follows a product's path from order to delivery to determine the current conditions. A future-state map shows the opportunities for improvement identified in the current-state map to achieve a higher level of performance at some future point.

Lean improves the process with a rich stew of programs, (some derived from Japanese philosophies) such as 5-S, Kaizen, self-empowered teams, cross training, visual process control, Total Productive Maintenance, Error Proofing and others. It is a "shotgun" approach to making money and cutting costs. Using a variety of processes helps ensure success: even if one falls short, everyone involved is doing so much to improve operations that, surely, something will turn out well! Accident prevention benefits as a side effect when Lean is done right. Let's review some of the elements of Lean that have accident prevention aspects.

5-S stands for "Sort, Straighten, Shine, Standardize and Sustain" or some other variation on the original Japanese terms. Safety benefits because the 5-S Methodology presents a disciplined program for cleaning, sorting, removing unused items and organizing remaining items. The housekeeping improvements are self-explanatory.

Visual Process Control lowers the learning curve for new-hires and makes it easier to keep things organized. That can benefit safety as well. Many workplaces have long-running problems such as blocked exits, lost equipment or pallets left in walking areas that can be eliminated with Visual Process Control.

Metrics and accountability for team members become a part of the culture, and it's not too hard to include safety measurables in this process (for supervisors, for example, metrics could be the number of safety contacts, accident investigations, employee training sessions, etc.) This raises the importance of the actions associated with the metrics. It is an essential element for integrating safety into daily activities.

Kaizen means employee involvement driven from the top down (a boon for safety). The value of employee input is generally accepted by the safety profession due to workers' intimate knowledge of their jobs. The inevitable greater acceptance of changes developed by those affected by them is also valuable. Buy-in can vastly improve the chance of success, just like a lack of buy-in can doom good ideas to failure.

Cross Training is promoted in Lean. It's needed to help adjust staffing levels to customer demand for product. This helps sell beneficial job rotations to supervisors who might have previously resisted implementing rotations when the only advocate in the company was the safety manager.

The trick is making sure that rotations follow a plan that helps reduce the effects of work stresses. This doesn't happen by itself. The safety professional's job is to get involved and make sure that the rotation system takes job stresses into account and rotates in a way that alternates work/rest cycles for the various muscle and tendon groups.

Finally, the essential starting element of Lean, Value Stream Mapping, helps reduce non-productive activity. Point-of-use racks eliminate long reaches for parts. Reducing reaches for parts also sounds a lot like sensible ergonomic change. Stress levels can drop, too. We may not have the freedom to slow a process down to reduce the risk of repetitive motion disorders, but reducing tasks per cycle accomplishes the same thing.

Error-proofing (known in Japan as Poka-Yoke) eliminates scrap and rejected products. Smarter machines stop work before bad parts are produced. Since less of the effort goes into unusable product and rework, the total labor that goes into producing a certain batch of usable product is minimized. Less labor means less stress and fewer chances to get hurt.

Errors and associated waste can be substantial. In one engine parts plant I worked in, the reject rate was up to a whopping 28 percent. Each reject part took just as many hours of effort as the good ones, and there was extra labor needed to inspect and do the rework. This means that about a quarter of their labor cost was waste. Chopping the reject rate down eliminated the stress associated with the wasted hours.

Get Involved

As you can see, all of the improvement programs working together can make a safer, more productive and efficient workplace that is better equipped to compete in the global economy. It can provide an excellent return on the investment of time and resources. What can you do to take full advantage of this windfall? Get involved and make sure that safety has a substantial role. Make sure that you add value to the process.

The involvement of a safety professional can make a huge difference. Some of the improvement processes can tend to get production-focused when everyone involved is a "production person." Nothing wrong with that, but involving safety in the processes can help production both indirectly and directly.

Indirectly, a safer workplace with fewer hazards requires less training on being cautious and a shorter learning curve... imagine how difficult it must have been to work safely in a 19th-century environment with unguarded pulley belts flailing, work platforms without guardrails, and open pits of hazardous chemicals. Less danger means fewer accidents, less administrative work to resolve claims and less lost productivity. Those are general improvements that have occurred over a long time. What are some of the specific areas with direct potential to add value?

Direct benefit can come from enhanced efficiency from ergonomic improvements, for example. Provide ergonomics assistance during the value stream mapping phase. Good ergonomics work always seems to help efficiency and productivity. Incorporate safety concerns into visual process control layouts. Include safety-critical items in total productive maintenance.

"A lean transformation naturally leads to an improvement in safety," says Chet Marchwinski, communications director at the Lean Enterprise Institute, a nonprofit training, research and publishing organization. "That's because some of the biggest improvement gains during the transformation often come from the lean tool known as standard work, which includes safety as a key element. Basically, standard work is the most efficient work flow considering quality, quantity, safety and cost. It consists of three elements:

1. Takt time matches the time to produce a part or finished product to the pace of sales and is the basis for allocating work among workers.

2. Standard in-process inventory the minimum number of parts, including units in machines, required to keep a cell or process moving.

3. Standard work sequence the order in which a worker performs tasks at various processes.

How can a safety professional get involved in this process? Integrate relevant safety items into standard work procedures. Push fair safety metrics into accountability systems to ease the process of improving behaviors. Participate in Kaizen events so safety aspects do not get overlooked. Maximize use of cross training opportunities to promote a useful workstation rotation scheme, perhaps using a color-coding system based on job demands evaluations by a physical therapist. Share ideas for error-proofing because fewer errors means less total work to produce the same amount of good product. Come up with some in-house ergonomics standards to be shared with engineers; redesign of existing equipment is a form of waste (you already paid once to design it) that in-house safety and ergo standards for new equipment can prevent.

Most of all, downtime is a form of waste. You as a safety professional are integral to preventing human downtime (days away from work or reduced productivity in the form of restricted work). You should be a key player, because human downtime is very costly. Think of Lean as an opportunity, and it might turn out to be one for you.

Contributing Editor William H.Kincaid, P.E., CSP, is a vice president and senior loss control consultant for Lockton Insurance Cos. in St. Louis. Before becoming a consultant, he was an OSHA safety engineer specializing in ergonomics, "significant cases" and fatality inspections. He earned his B.S. in mechanical engineering from Washington University in St. Louis.

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