Inside Dental Technology
February 2015
Volume 6, Issue 2

Speaking Lean—Use the Right Definitions

Be on the same page with all your key players in the laboratory

By Bob Yenkner

Lean thinking and practices continue to expand into laboratories, and more businesses adapt Lean as an operating philosophy. But the words and the definitions run a risk for being corrupted, adapted, or mutated to meet the laboratories’ culture or understanding of Lean. The Glossary of Lean Terms is large; some of the words you will use often, many you will have to constantly look up to refresh your memory. Here are a few terms and definitions:


Producing more than one piece of an item and then moving those items forward to the next operation before they are all actually needed there. Thus, items need to wait in a queue for the technician to begin work.

Bottleneck (BN)

A resource with a capacity that is less than or equal to the market demand. (It is occupied 24-7, 365 days a year.)

Capacity-constrained resource (CCR)

A resource between a BN and a non-bottleneck. The resource has periods of overcapacity (erratic demand, breakdowns, lack of material).

Continuous flow production

Items are produced and moved from one processing step to the next one piece at a time. Each process makes only the one piece that the next process needs, and the transfer batch size is one. Also called single-piece flow or one-piece flow. (See batch-and-queue.)


Going to the place (where the problem exists) to see the actual situation for understanding. The first step in problem solving is to clearly and deeply understand the situation through personal observation, data gathering, and analysis. The guiding principle is to take nothing for granted and know what you are talking about, and that is achieved through gaining firsthand knowledge of the problem or issue.


Continuous, incremental improvement of an activity to create more value with less waste. "Kaizen blitz" refers to a team approach to quickly tear down and rebuild a process or solve a problem to function more efficiently.


A signaling device that gives instruction for production or conveyance of items in a pull system. Examples of a kanban are a space on the floor, a container, a card, an empty shelf, an andon light, and an electronic signal.


A philosophical approach to developing flexible, responsive processes capable of providing your customers with what they want, in the amount they need, exactly when they want it.

Non-bottleneck (NBN)

A resource with a capacity that is greater than the market demand. (It is available 24-7, but not always occupied.)

Non-value add (NVA)

Activities that take time, resources, or space, but do not transform or add to the customer’s desired or perceived value of a product. Waste is NVA, and so too are inspection, test, rework, and quality audit. Many businesses will argue that these activities are VA, because they are either required by the customer or are a necessary evil. But why does the customer require inspection and test? If processes were robust (without errors), would these actions be required? Reduction or elimination of this NVA activity would reduce cost and cycle time and favorably impact customer satisfaction.


A mistake-proofing device, method, or procedure to prevent a defect from occurring during the process. Poka-yoke devices are specifically designed to eliminate mistakes before they become a defect. Focus is on prevention and detection before the error proceeds downstream and becomes a defect.

Root-cause analysis

Any structured approach to identify the factors that resulted in the nature, the magnitude, the location, and the timing of the harmful outcomes (consequences) of one or more past events. The goal is to identify which behaviors, actions, inactions, or conditions need to be changed to prevent recurrence of similar harmful outcomes and to identify the lessons to be learned to promote the achievement of better consequences.

6S (workplace organization)

Six terms utilized to create a workplace suited for visual control and lean production. "Sort" means to separate needed tools, parts, and materials from unneeded items and to remove the latter. "Stabilize" means to neatly arrange and identify parts and tools for ease of use. "Shine" refers to conducting a cleanup campaign. "Standardize" means share established standards, make standards obvious, and conduct 6S at frequent intervals to maintain a workplace in perfect condition. "Safety" means to promote and maintain an accident-free workplace. "Sustain" means to form the habit of always following the first 5S’s.

Standard work

A precise description of each work activity specifying cycle time, takt time (maximum time to produce a product to meet demand), work sequence of specific tasks, and the minimum inventory of parts on hand needed to conduct the activity. Standard work is not the same as work standards (rate per hour at a specific task).

Value-add (VA)

Activities that transform or shape products to meet the true customer expectations. Many people tend to include the words “what the customer is willing to pay for,” which makes this an accounting definition, not an operational definition. If this were the case, why bother to improve productivity at all if the customer is paying for a finished unit?

Visual management

Visual management focuses on timely sharing of information to assist with stability in the process, maintainence of employee awareness, and sharing of key pieces of information. Information to be shared typically takes two forms: operating information such as sales per month, remake amounts, units per department, and on-time delivery statistics, and work instructions to perform a specific task, using both pictures and text.

Waste (muda)

Anything that does not add value to the product is unnecessary and must be reduced or eliminated. Eight types are defects, overproduction, waiting, not using employee brainpower (creativity), transportation (moving material), inventory, motion, and extra processing.

The terms as discussed are taken from various, authoritative Lean sources. As your business embarks on a Lean journey, acquire a standard glossary so that everyone can speak the same language.

Bob Yenkner is the owner of Practical Process Improvement (PPI) in Higganum, CT.

Read "The Building Blocks of Sales Success" by Deborah Curson-Vieira at insidedentaltech.com/idt747.

© 2021 AEGIS Communications | Privacy Policy