The more visible abnormalities, the more apt employees are to fix them.

Dr. Shigeo Shingo wrote: “Unfortunately, real waste lurks in forms that do not look like waste. Only through careful observation and goal orientation can waste be identified. We must always keep in mind the greatest waste is the waste we don’t see.”

The validity of Dr. Shingo’s statement drives the use of visual systems at Celestica – an important tool within our Lean enterprise. Visual systems provide employees with immediate visual access to important, timely information: knowledge that employees can leverage to react quickly to challenges through continuous improvement.

An example of a basic visual system is a traffic light. When you approach an intersection, you immediately know how, and if, you should proceed based on the color of the signal. It enables you to make the best possible choice. In a Lean manufacturing environment, visual systems make information visible to the people who need it to do their jobs effectively. They communicate information on a number of things – including reliability, quality, safety and productivity. They can also reduce the learning curve for new or temporary employees and help overcome language barriers.

From a business perspective, the greatest function of a visual system is its ability to illuminate abnormalities. Once employees see something abnormal, they become uncomfortable with the current state. This creates the tension that spurs improvement.

Since a certain level of abnormalities drives manufacturing costs, the more abnormalities we can see and eliminate, the better. We want employees to feel dissatisfied with the current state and, with management support, fix the issues – resulting in more efficient operations, better quality, lower cost, happier employees, better delivery, and more capacity for growth.

In a cellular manufacturing environment, visual systems are used in a number of ways: to see which product model a line is running, to help control the amount of standard work in process (WIP), to let operators know when to signal for more material, and to indicate where one operator starts and finishes a job – clearly establishing the work cycle. We use visual systems to ensure production is streamlined and efficient. Many obstacles can arise when attempting to run single-piece flow in a manufacturing cell; the more quickly problems are identified, the more problems can be fixed, and the longer single piece flow can be sustained.

At Celestica, manufacturing cells post and update charts that track progress. Visible to all cell operators, the charts quickly alert employees to any abnormalities, or gaps, between their plan and actual results. The charts also indicate where gaps are occurring: yield, downtime, etc. Unsatisfied with the problems conveyed by the visual system, the team can concentrate on the highest recurring issue and ensure continuous improvement activity is focused on driving improvements in that area.

The more repeatable and routine the work, the more opportunities there are for visual systems to have a positive impact. The more visible the abnormalities, the more apt employees are to creatively drive improvements that generate better and more predictable results. Visual systems also make it easier to acknowledge and celebrate successes, such as the number and scope of improvements made.

To use visual systems most effectively, it’s important to take a few things into consideration, including:

The physical properties of the visual system. When communicating visually, we must consider the shape, size, color and information displayed to determine what will be most effective and have the most impact on employees. For example, ensure signs are large enough for everyone to read from each workstation, or use color to help convey a message (i.e., green for relax, yellow for worry, red for panic). Let the team using the information determine where to post the visual system.

Less is more. Based on 5S principles, only pertinent information should be displayed. Avoid clutter. People should be able to grasp the information conveyed within a few seconds. A speed limit sign that reads “Maximum 55 mph” is much easier to grasp than one crowded with information, reading, “The speed limit on this highway is maximum 55 miles per hour as measured by your car’s speedometer and don’t forget to buckle up.” I exaggerate, of course, but there’s an element of truth to the example.

On the manufacturing floor, visual controls often need to be frequently updated. Keep visual systems simple, clear and quick to minimize time spent reading, understanding and updating information.

Who has access to visual systems. Make visual systems available to everyone involved in the work. The information conveyed should not be privy to one or two people. In fact, anyone who walks onto the factory floor should be able to quickly grasp the situation.

For example, one of our sites has arrows on the floor indicating product flow. In another, cells manufacturing multiple models of a product identify each variation with a picture of an animal instead of a lengthy model number. Since all inventory is labeled this way, it takes just a quick glance for material handlers to know exactly which materials to deliver to which line, and the line managers and teams to know exactly what product they’re building.

The key is getting the right amount of information to the right people at the right time and avoiding giving too much (or too little) information to the wrong people at the wrong time.

It’s not always pretty. Honesty is the driving force behind visual systems in a Lean environment. It makes abnormalities and errors visible to everyone who passes by the work area. While this makes people uncomfortable with the current state, this is the true purpose of visual systems. The speedy recognition of abnormalities and issues is the first step to driving change, then continuous improvement, and ultimately, the celebration of success.

Start simple. The more experience a manufacturing site has with visual systems, the better the systems become. Posting a great deal of information in a new site can be overwhelming for employees and may actually drive confusion more than continuous improvement. The best approach: Start with something simple and manageable based on where your site is in its Lean journey. The more you use visual systems to drive positive change, the more the systems will evolve. Employee knowledge becomes more sophisticated and people see more opportunities for making improvements.

Ensure a management system is in place. Without a management system in place to drive sustained progress, visual systems are pointless. For instance, a cell that tracks output vs. plan may understand where challenges lie, but if there is no management system in place by which to tackle the problem, there will be no improvement. Visual systems must be up to date, well maintained and, most importantly, actionable!

As you can see, visual systems are an empowering tool. This is more evident when you consider the alternative.

Often, in a non-Lean work environment, information pertaining to performance is only visible to management and not readily available to all employees involved in the work. This information is often complicated or functionally driven so only a limited number of employees can truly understand and use it. Errors and abnormalities are not openly shared to maintain the perception that everything is under control.

The goal of any Lean enterprise is to use visual systems to be good, rather than to look good. Being good means using visual systems in tandem with other problem-solving tools to foster the most effective, efficient and profitable manufacturing environment.

Robert Hemmant is global Lean architect at Celestica (celestica.com). His column appears bimonthly.

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