Yellow Belt Glossary

Question 1

Andon

Answer 1

A visual management tool that highlights the status of operations
in an area at a single glance and that signals whenever an
abnormality occurs.

Question 2

Batch-and-Queue

Answer 2

A mass production approach to operations in which large lots
(batches) of items are processed and moved to the next process
—regardless of whether they are actually needed—where they
wait in a line (a queue).

Question 3

Cell

Answer 3

The location of processing steps for a product immediately adjacent
to each other so that parts, documents, etc., can be processed in
very nearly continuous flow, either one at a time or in small batch
sizes that are maintained through the complete sequence of
processing steps.

A U shape (shown below) is common because it minimizes walking
distance and allows different combinations of work tasks for
operators. This is an important consideration in lean production
because the number of operators in a cell will change with changes
in demand. A U shape also facilitates performance of the first and
last steps in the process by the same operator, which is helpful in
maintaining work pace and smooth flow.

Many companies use the terms cell and line interchangeably.
There is a school of thought that material should flow through cells
in a right-to-left direction relative to the operator, because more
people are right handed and it is more efficient and natural to work
from right to left. However, many efficient processes flow to the left
and many flow to the right. Simply evaluate on a case-by-case
basis whether a particular direction makes more sense.

Question 4

Continuous Flow

Answer 4

Producing and moving one item at a time (or a small and consistent
batch of items) through a series of processing steps as continuously
as possible, with each step making just what is requested by the
next step.
Continuous flow can be achieved in a number of ways, ranging from
moving assembly lines to manual cells. It also is called one-piece
flow, single-piece flow, and make one, move one.

Question 5

Cycle Time

Answer 5

The time required to produce a part or complete a process, as timed
by actual measurement.
Cycle Time—Related Terms Involving Time
Effective Machine Cycle Time
Machine cycle time plus load and unload time, plus the result of
dividing changeover time by the number of pieces between changeovers.
For example, if a machine has a cycle time of 20 seconds, plus
a combined load and unload time of 30 seconds, and a changeover
time of 30 seconds divided by a minimum batch size of 30, the
Effective Machine Cycle Time is 20+30+(30/30) or 1 = 51 seconds.
Machine Cycle Time
The time a machine requires to complete all of its operations
on one piece.

Question 6

Downtime

Answer 6

Production time lost due to planned or unplanned stoppages.
Planned downtime includes scheduled stoppages for activities such
as beginning-of-the-shift production meetings, changeovers to
produce other products, and scheduled maintenance. Unplanned
downtime includes stoppages for breakdowns, machine adjustments,
materials shortages, and absenteeism.

Question 7

Efficiency

Answer 7

Meeting exact customer requirements with the minimum amount
of resources.
Apparent Efficiency vs. True Efficiency
Taiichi Ohno illustrated the common confusion between apparent
efficiency and true efficiency with an example of 10 people producing
100 units daily. If improvements to the process boost output to 120
units daily, there is an apparent 20 percent gain in efficiency. But
this is true only if demand also increases by 20 percent. If demand
remains stable at 100 the only way to increase the efficiency of the
process is to figure out how to produce the same number of units
with less effort and capital. (Ohno 1988, p. 61.)

Question 8

First In, First Out (FIFO)

Answer 8

The principle and practice of maintaining precise production and
conveyance sequence by ensuring that the first part to enter a
process or storage location is also the first part to exit. (This ensures
that stored parts do not become obsolete and that quality problems
are not buried in inventory.) FIFO is a necessary condition for pull
system implementation.
The FIFO sequence often is maintained by a painted lane or physical
channel that holds a certain amount of inventory. The supplying
process fills the lane from the upstream end while the customer
process withdraws from the downstream end. If the lane fills up, the
supplying process must stop producing until the customer consumes
some of the inventory. This way the FIFO lane can prevent the
supplying process from overproducing even though the supplying
process is not linked to the consuming process by continuous flow
or a supermarket.
FIFO is one way to regulate a pull system between two decoupled
processes when it is not practical to maintain an inventory of all
possible part variations in a supermarket because the parts are
one-of-a-kind, have short shelf lives, or are very expensive but
required infrequently. In this application, the removal of the one
part in a FIFO lane by the consuming process automatically triggers
the production of one additional part by the supplying process.

Question 9

Five Whys

Answer 9

The practice of asking why repeatedly whenever a problem is
encountered in order to get beyond the obvious symptoms to
discover the root cause.
For instance, Taiichi Ohno gives this example about a machine
that stopped working (Ohno 1988, p. 17):
1. Why did the machine stop?
There was an overload and the fuse blew.
2. Why was there an overload?
The bearing was not sufficiently lubricated.
3. Why was it not lubricated?
The lubrication pump was not pumping sufficiently.
4. Why was it not pumping sufficiently?
The shaft of the pump was worn and rattling.
5. Why was the shaft worn out?
There was no strainer attached and metal scraps got in.
Without repeatedly asking why, managers would simply replace
the fuse or pump and the failure would recur. The specific number
five is not the point. Rather it is to keep asking until the root cause
is reached and eliminated.

Question 10

Error-Proofing or Poka-Yoke

Answer 10

Methods that help operators avoid mistakes in their work caused
by choosing the wrong part, leaving out a part, installing a part
backwards, etc. Also called mistake-proofing, poka-yoke (errorproofing)
and baka-yoke (fool-proofing).
Common examples of error-proofing include:
• Product designs with physical shapes that make it impossible
to install parts in any but the correct orientation.
• Photocells above parts containers to prevent a product from
moving to the next stage if the operator’s hands have not
broken the light to obtain necessary parts.

Question 11

Gemba

Answer 11

The Japanese term for “actual place,” often used for the shop
floor or any place where value-creating work actually occurs; also
spelled genba.
The term often is used to stress that real improvement requires a
shop-floor focus based on direct observation of current conditions
where work is done. For example, standardized work for a
machine operator cannot be written at a desk in the engineering
office, but must be defined and revised on the gemba.

Question 12

Inventory

Answer 12

Materials (and information) present along a value stream between
processing steps.
Physical inventories usually are categorized by position in the value
stream and by purpose. Raw materials, work-in-process, and finished
goods are terms used to describe the position of the inventory within
the production process. Buffer stocks, safety stocks, and shipping
stocks are terms used to describe the purpose of the inventory.
Since inventory always has both a position and a purpose (and
some inventories have more than one purpose) the same items
may be, for example, finished goods and buffer stocks. Similarly,
the same items may be raw materials and safety stocks. And some
items even may be finished goods, buffer stocks, and safety stocks
(particularly if the value stream between raw materials and finished
goods is short).
The size of the buffer and safety inventory levels will depend on
the amplitude of the variations in downstream demand (creating
the need for buffer stock) and the capability of the upstream
process (creating the need for safety stock). Good lean practice is
to determine the inventory for a process and to continually reduce
it when possible, but only after reducing downstream variability
and increasing upstream capability. Lowering inventory without
addressing variability or capability will only disappoint the customer
as the process fails to deliver needed products on time.
To avoid confusion, it is important to define each type of inventory
carefully.

Question 13

Inventory Turns

Answer 13

A measure of how quickly materials are moving through a facility
or through an entire value stream, calculated by dividing some
measure of cost of goods by the amount of inventory on hand.
Probably the most common method of calculating inventory turns
is to use the annual cost of goods sold (before adding overhead for
selling and administrative costs) as the numerator divided by the
average inventories on hand during the year. Thus:
Annual cost of goods sold
Inventory turns =
Average value of inventories during the year
Using the cost of goods rather than sales revenues removes one
source of variation unrelated to the performance of the production
system—fluctuations in selling prices due to market conditions.
Using an annual average of inventories rather than an end-ofthe-
year figure removes another source of variation—an artificial
drop in inventories at the end of the year as managers try to show
good numbers.
Inventory turns can be calculated for material flows through value
streams of any length. However, in making comparisons remember
that turns will decline with the length of the value stream, even if
performance is equally “lean” all along the value stream. For example,
a plant performing only assembly may have turns of 100 or more
but when the parts plants supplying the assembly plant are added
to the calculation, turns often will fall to 12 or fewer. And if materials
are included all the way back to their initial conversion—steel, glass,
resins, etc.—turns often will fall to four or fewer. This is because the
cost of goods sold at the most downstream step doesn’t change but
the amount of materials in inventories grows steadily as we add
more and more facilities to our calculation.
Inventory turns are a great measure of a lean transformation if the
focus is shifted from the absolute number of turns at each facility
or in the entire value stream to the rate of increase in turns. Indeed,
if turns are calculated accurately using annualized averages of
inventories, they can be “the one statistic that can’t lie.”

Question 14

Jidoka

Answer 14

Providing machines and operators the ability to detect when
an abnormal condition has occurred and immediately stop work.
This enables operations to build in quality at each process and
to separate men and machines for more efficient work. Jidoka
is one of the two pillars of the Toyota Production System along
with just-in-time.
Jidoka highlights the causes of problems because work stops
immediately when a problem first occurs. This leads to improvements
in the processes that build in quality by eliminating the root causes
of defects.
Jidoka sometimes is called autonomation, meaning automation
with human intelligence. This is because it gives equipment the
ability to distinguish good parts from bad autonomously, without
being monitored by an operator. This eliminates the need for
operators to continuously watch machines and leads in turn to
large productivity gains because one operator can handle several
machines, often termed multiprocess handling.
The concept of jidoka originated in the early 1900s when Sakichi
Toyoda, founder of the Toyota Group, invented a textile loom that
stopped automatically when any thread broke. Previously, if a thread
broke the loom would churn out mounds of defective fabric, so each
machine needed to be watched by an operator. Toyoda’s innovation
let one operator control many machines. In Japanese, jidoka is a
Toyota-created word pronounced exactly the same (and written in
kanji almost the same) as the Japanese word for automation, but
with the added connotations of humanistic and creating value.

Question 15

Just-in-Time (JIT)

Answer 15

A system of production that makes and delivers just what is needed,
just when it is needed, and just in the amount needed. JIT and jidoka
are the two pillars of the Toyota Production System. JIT relies on
heijunka as a foundation and is comprised of three operating
elements: the pull system, takt time, and continuous flow.
JIT aims for the total elimination of all waste to achieve the best
possible quality, lowest possible cost and use of resources, and the
shortest possible production and delivery lead times. Although simple
in principle, JIT demands discipline for effective implementation.
The idea for JIT is credited to Kiichiro Toyoda, the founder of Toyota
Motor Corporation, during the 1930s. As manager of the machine
shop at Toyota’s main plant, Taiichi Ohno said his first steps toward
achieving JIT in practice came in 1949–50. (Ohno 1988, p. 31.)

Question 16

Kaikaku

Answer 16

Radical, revolutionary improvement of a value stream to quickly
create more value with less waste; sometimes called kakushin.
One example would be moving equipment over a weekend so that
products formerly fabricated and assembled in batches in isolated
process villages are made in single-piece flow in a compact cell.
Another example would be quickly switching from stationary to
moving assembly for a large product such as a commercial airliner.
Also called breakthrough kaizen, in comparison with more gradual,
step-by-step kaizen.

Question 17

Kaizen

Answer 17

Continuous improvement of an entire value stream or an individual
process to create more value with less waste.
There are two levels of kaizen (Rother and Shook 1999, p. 8):
1. System or flow kaizen focusing on the overall value stream.
This is kaizen for management.
2. Process kaizen focusing on individual processes.
This is kaizen for work teams and team leaders.
Value-stream mapping is an excellent tool for identifying an entire
value stream and determining where flow and process kaizen
are appropriate.

Question 18

Kanban

Answer 18

A kanban is a signaling device that gives authorization and instructions
for the production or withdrawal (conveyance) of items in a pull
system. The term is Japanese for “sign” or “signboard.”
Kanban cards are the best-known and most common example
of these signals. They often are slips of card stock, sometimes
protected in clear vinyl envelopes, stating information such as
part name, part number, external supplier or internal supplying
process, pack-out quantity, storage address, and consuming
process address. A bar code may be printed on the card for
tracking or automatic invoicing.
Besides cards, kanban can be triangular metal plates, colored
balls, electronic signals, or any other device that can convey
the needed information while preventing the introduction of
erroneous instructions.
Whatever the form, kanban have two functions in a production
operation: They instruct processes to make products and they
instruct material handlers to move products. The former use is
called production kanban (or make kanban); the latter use is
termed withdrawal kanban (or move kanban).
Production kanban tell an upstream process the type and quantity
of products to make for a downstream process. In the simplest
situation, a card corresponds to one container of parts, which the
upstream process will make for the supermarket ahead of the next
downstream process. In large batch situations—for example, a
stamping press with very short cycle times and long changeover
times—a signal kanban is used to trigger production when a
minimum quantity of containers is reached. Signal kanban often
are triangular in shape and thus often also called triangle kanban.
Although a triangle kanban is the standard used in lean manufacturing
to schedule a batch production process, it is only one type of signal
kanban. Other basic means of controlling batch operations include
pattern production and lot making.

Question 19

Lean Thinking

Answer 19

A five-step thought process proposed by Womack and Jones in
1996 to guide managers through a lean transformation. The five
principles are:
1. Specify value from the standpoint of the end customer by
product family.
2. Identify all the steps in the value stream for each product
family, eliminating whenever possible those steps that do
not create value.
3. Make the value-creating steps occur in tight sequence so the
product will flow smoothly toward the customer.
4. As flow is introduced, let customers pull value from the next
upstream activity.
5. As value is specified, value streams are identified, wasted
steps are removed, and flow and pull are introduced, repeat
this process again and continue it until a state of perfection
is reached in which perfect value is created with no waste.
(Adapted from Womack and Jones 1996, p. 10.)
In 2007, Womack and Jones simplified the five steps to these—
Purpose, Process, People:
Purpose: The primary purpose of any organization and first step in
any lean thought process is to correctly specify the value that the
customer seeks in order to cost-effectively solve the customer’s
problems so the organization can prosper.
Process: Once purpose is clarified, focus on the process (value stream)
used to achieve this objective. This is generally the combined result
of three processes: product and process development, fulfillment
from order to delivery, and support of the product and the customer
through the product’s useful life. These primary processes are made
possible by many secondary, supportprocesses inside the
organization and upstream.
The ideal process is one in which every step (action) is:
• Valuable: Meaning that the customer is willing to pay for the step
because it creates value and would object if the step was deleted.
• Capable: Producing a good result every time.
• Available: Being able to operate whenever needed.
• Adequate: Having the capacity to keep production in continuous flow.
• Flexible: Permitting a range of products within a product family
to move through a process without batching and delays.
In addition, in the ideal process the steps are linked by:
• Flow: So the good or service proceeds immediately from one
step to the next without stopping.
• Pull: So the next downstream step obtains just what it needs from
the next upstream step when continuous flow is not possible.
• Leveling: From some pacemaker point to smooth the operation
of the process while still addressing the needs of the customer.
People: After identifying the primary and support processes needed
to create value for the customer, make someone responsible for
each value stream. This value-stream manager must engage and
align the efforts of everyone touching each value stream to move it
steadily toward the customer while elevating performance from its
current state to an ever-better future state. Doing this requires:
• A master plan for the enterprise, often called strategy deployment.
• Frequent improvement cycles for each process, often performed
with A3 analysis embodying value-stream maps.
• Standard work with standard management for every step in
each process.

Question 20

Muda, Mura, Muri

Answer 20

Three terms often used together in the Toyota Production System
(and called the Three Ms) that collectively describe wasteful
practices to be eliminated.
Muda
Any activity that consumes resources without creating value for
the customer. Within this general category it is useful to distinguish
between type one muda, consisting of activities that cannot be
eliminated immediately, and type two muda, consisting of activities
that can be eliminated quickly through kaizen.
An example of type one muda is a rework operation after a paintbooth,
which is required to obtain a finish acceptable to the customer from
a paint process that is not highly capable. Because a completely
capable paint process for fine finishes has eluded manufacturers for
decades, it is not likely that this type of muda can be eliminated quickly.
An example of type two muda is multiple movements of products
and inventories between steps in a fabrication and assembly process.
These steps can be quickly eliminated in a kaizen workshop by moving
production equipment and operators into a smoothly flowing cell.

Mura
Unevenness in an operation; for example, a gyrating schedule not
caused by end-consumer demand but rather by the production system,
or an uneven work pace in an operation causing operators to hurry and
then wait. Unevenness often can be eliminated by managers through
level scheduling and careful attention to the pace of work.

Muri
Overburdening equipment or operators by requiring them to run
at a higher or harder pace with more force and effort for a longer
period of time than equipment designs and appropriate workforce
management allow.

Muda, Mura, and Muri in Conjunction
A simple illustration shows how muda, mura, and muri often are
related so that eliminating one also eliminates the others.
Suppose that a firm needs to transport six tons of material to its
customer and is considering its options. One is to pile all six tons
on one truck and make a single trip. But this would be muri because
it would overburden the truck (rated for only three tons) leading to
breakdowns, which also would lead to muda and mura.
A second option is to make two trips, one with four tons and the
other with two. But this would be mura because the unevenness
of materials arriving at the customer would create jam-ups on the
receiving dock followed by too little work. This option also would
create muri, because on one trip the truck still is overburdened,
and muda as well, because the uneven pace of work would cause
the waste of waiting by the customer’s receiving employees.
A third option is to load two tons on the truck and make three trips.
But this would be muda, even if not mura and muri, because the
truck would be only partially loaded on each trip.
The only way to eliminate muda, mura, and muri is to load the
truck with three tons (its rated capacity) and make two trips.

Question 21

Overall Equipment Effectiveness (OEE)

Answer 21

A total productive maintenance (TPM) measure of how effectively
equipment is being used.
OEE is calculated from three elements: The availability rate measures
downtime losses from equipment failures and adjustments as a
percentage of scheduled time. The performance rate measures
operating speed losses—running at speeds lower than design speed
and stoppages lasting a few seconds. The quality rate expresses
losses due to scrap and rework as a percentage of total parts run.
These elements are multiplied to obtain OEE:
Availability Rate x Performance Rate x Quality Rate = OEE
If Availability is 90%, Performance is 95%, and Quality is 99% then
0.90 x 0.95 x 0.99 = 84.6% OEE
OEE typically focuses on what are termed the six major losses—
failures, adjustments, minor stoppages, reduced operating speeds,
scrap, and rework—but some companies add other measures judged
important to their business.

Question 22

Overproduction

Answer 22

Producing more, sooner or faster than is required by the next
process. Ohno considered overproduction to be the most grievous
form of waste because it generates and hides other wastes, such as
inventories, defects, and excess transport.

Question 23

Pitch

Answer 23

The amount of time needed in a production area to make one
container of products.
The formula for pitch is:
takt time x pack-out quantity = pitch
For example, if takt time (available production time per day divided
by customer demand per day) is one minute and the pack-out
quantity is 20, then: 1 minute x 20 pieces = pitch of 20 minutes
Pitch, in conjunction with the use of a heijunka box and material
handling based on paced withdrawal, helps set the takt image and
pace of a facility or process.
Note that the term pitch also is sometimes used to indicate the
span or time of a person’s job.

Question 24

Production Analysis Board

Answer 24

A display—often a large whiteboard—located beside a process to
show actual performance compared with planned performance.
The board in the illustration on p. 79 shows the performance of a
process on an hourly basis with planned versus actual production.
When production does not correspond to the plan, the problem is
recorded and a cause is sought.
Note that a process regulated by pull signals rather than a preset
schedule will record the amounts requested by the next downstream
process, which may vary from plan during a shift or day, and compare
the requested amounts with actual production.
A production analysis board can be an important visual management
tool, particularly as a firm begins its transformation to lean production.
However, it is important to understand that the appropriate use for
the production analysis board is as a problem-identification and
problem-solving tool and not, as often is misunderstood, as a tool
for scheduling production. The tool also is sometimes called a
production control board, a progress control board, or—more
appropriately—a problem-solving board.

Question 25

Red Tagging

Answer 25

Labeling unneeded items for removal from a production or office
area during a Five S exercise.
Red tags are attached to unneeded tools, equipment, and supplies.
Tagged items are placed in a holding area where they are evaluated
for other uses within a facility or company. Those with no alternative
uses are discarded. Red tagging helps achieve the first S of the Five S
exercise, which calls for separating needed from unneeded items.

Question 26

Setup Reduction

Answer 26

The process of reducing the amount of time needed to changeover
a process from the last part for the previous product to the first good
part for the next product.
The six basic steps in setup reduction are:
1. Measure the total setup time in the current state.
2. Identify the internal and external elements, calculating
the individual times.
3. Convert as many of the internal elements to external
as possible.
4. Reduce the time for the remaining internal elements.
5. Reduce the time for the external elements.
6. Standardize the new procedure.

Question 27

Single Minute Exchange of Dies (SMED)

Answer 27

A process for changing over production equipment from one part
number to another in as little time as possible. SMED refers to the target
of reducing changeover times to a single digit, or less than 10 minutes.
Shigeo Shingo’s key insights about setup reduction, which were
developed in the 1950s and 1960s, were separating internal setup
operations—which can be done only when a machine is stopped
(such as inserting a new die)—from external operations that can
be performed while the machine is running (such as transporting
the new die to the machine), and then converting internal setup
operations to external operations. (Shingo 1985, p. 21–25.)

Question 28

Six Sigma

Answer 28

Six Sigma
A quality standard of just 3.4 defects per one million opportunities;
99.9996% perfect.
Six sigma methodologies emphasize mathematical and statistical
tools to improve the quality of processes that are already under
control. Application follows a five-step process of define, measure,
analyze, improve, and control often referred to as DMAIC.
Motorola conceived the six sigma technique in 1986 as a way to
achieve the company’s improvement goals in manufacturing and
support functions. The term refers to the number of standard
deviations a point is away from the mean point in a bell curve. It
often is represented as 6.
Many lean thinkers apply six sigma techniques to solve stubborn
quality problems in value-adding processes that already are under
control and where an analysis of the overall value-stream has
eliminated nonvalue-adding processes.

Question 29

Spaghetti Chart

Answer 29

A diagram of the path taken by a product as it travels through the
steps along a value stream. So called because in a mass production
organization the product’s route often looks like a plate of spaghetti.

Question 30

Standard Work

Answer 30

Establishing precise procedures for each operator’s work in a
production process, based on three elements:
1. Takt time, which is the rate at which products must
be made in a process to meet customer demand.
2. The precise work sequence in which an operator
performs tasks within takt time.
3. The standard inventory, including units in machines,
required to keep the process operating smoothly.
Standardized work, once established and displayed at workstations,
is the object of continuous improvement through kaizen. The benefits
of standardized work include documentation of the current process
for all shifts, reductions in variability, easier training of new
operators, reductions in injuries and strain, and a baseline for
improvement activities.
Three basic forms (shown on pp. 93–94) commonly are utilized
in creating standardized work. These are used by engineers and
front-line supervisors to design the process and by operators to
make improvements in their own jobs.
1. Process Capacity Sheet
This form is used to calculate the capacity of each machine
in a linked set of processes (often a cell) in order to confirm
true capacity and to identify and eliminate bottlenecks. This
form determines such factors as machine cycle times, tool
setup and change intervals, and manual work times.
2. Standardized Work Combination Table
This form shows the combination of manual work time, walk time,
and machine processing time for each operator in a production
sequence. This form provides more detail and is a more precise
process design tool than the operator balance chart (shown on
p. 67). The completed table shows the interactions between
operators and machines in a process and permits the recalculation
of operator work content as takt time expands and contracts
over time.

Question 31

Takt Time

Answer 31

The available production time divided by customer demand.
For example, if a widget factory operates 480 minutes per day and
customers demand 240 widgets per day, takt time is two minutes.
Similarly, if customers want two new products per month, takt time is
two weeks. The purpose of takt time is to precisely match production
with demand. It provides the heartbeat of a lean production system.
Takt time first was used as a production management tool in the
German aircraft industry in the 1930s. (Takt is German for a precise
interval of time such as a musical meter.) It was the interval at
which aircraft were moved ahead to the next production station. The
concept was widely utilized within Toyota in the 1950s and was in
widespread use throughout the Toyota supply base by the late 1960s.
Toyota typically reviews the takt time for a process every month,
with a tweaking review every 10 days.

Question 32

Total Productive Maintenance (TPM)

Answer 32

A set of techniques, originally pioneered by Denso in the Toyota
Group in Japan, to ensure that every machine in a production
process always is able to perform its required tasks.
The approach is termed total in three senses. First, it requires the
total participation of all employees, not only maintenance personnel
but line managers, manufacturing engineers, quality experts, and
operators. Second, it seeks total productivity of equipment by
focusing on all of the six major losses that plague equipment:
downtime, changeover time, minor stops, speed losses, scrap,
and rework. Third, it addresses the total life cycle of equipment
to revise maintenance practices, activities, and improvements in
relation to where equipment is in its life cycle.
Unlike traditional preventive maintenance, which relies on
maintenance personnel, TPM involves operators in routine
maintenance, improvement projects, and simple repairs. For
example, operators perform daily activities such as lubricating,
cleaning, tightening, and inspecting equipment.

Question 33

Value

Answer 33

The inherent worth of a product as judged by the customer and
reflected in its selling price and market demand.
The value in a typical product is created by the producer through a
combination of actions, some of which produce value as perceived
by the customers and some of which are merely necessary given
the current configuration of the design and production process.
The objective of Lean Thinking is to eliminate the latter class of
activities while preserving or enhancing the first set.
Value-Creating
Any activity that the customer judges of value. A simple test as
to whether a task and its time is value-creating is to ask if the
customer would judge a product less valuable if this task could be
left out without affecting the product. For example, rework and
queue time are unlikely to be judged of any value by customers,
while actual design and fabrication steps are.
Nonvalue-Creating
Any activity that adds cost but no value to the product or service
as seen through the eyes of the customer.

Question 34

Muda

Answer 34

Muda
Any activity that consumes resources without creating value for
the customer. Within this general category it is useful to distinguish
Example of a Milk Run
between type one muda, consisting of activities that cannot be
eliminated immediately, and type two muda, consisting of activities
that can be eliminated quickly through kaizen.
An example of type one muda is a rework operation after a paintbooth,
which is required to obtain a finish acceptable to the customer from
a paint process that is not highly capable. Because a completely
capable paint process for fine finishes has eluded manufacturers for
decades, it is not likely that this type of muda can be eliminated quickly.
An example of type two muda is multiple movements of products
and inventories between steps in a fabrication and assembly process.
These steps can be quickly eliminated in a kaizen workshop by moving
production equipment and operators into a smoothly flowing cell.

Question 35

Work

Answer 35

Human actions (motions) involved in producing products. These
actions can be divided into three categories:
1. Value-Creating: Movements directly necessary for making
products, such as welding, drilling, and painting.
2. Incidental Work: Motions that operators must perform to make
products but that do not create value from the standpoint of the
customer, such as reaching for a tool or clamping a fixture.