|Quality Management and Safety Engineering (BSc) - MST 326|
Quality Circles. Kaizen (continuous improvement). Poka-Yoke.
Many types of teams [1, pp.310-311] exist within commercial
- management teams: senior personnel from various functions that co-ordinate
the activity of the workforce.
- problem-solving teams: people gathered together to solve a specific
problem within a finite period.
- project teams: a group with a specific mission to develop a new product or
- quality circles: teams of workers and supervisors who meet regularly to
address workplace issues, especially productivity and quality.
- virtual teams; selected individual across the company who communicate via
the computer network
- work teams: teams organised to perform an entire job (rather than
assembly-line type work),
when work teams are empowered, they are referred to as self-managed teams.
Quality Control Circles (QCC), now referred to as Quality Circles
The concept of Quality Circles is attributed to Kaoru Ishikawa in Japan in
the 1950s. QC usually
consist of a small group of personnel from the same department or function
within the company who volunteer to meet regularly to identify, solve and implement solutions
to work-related problems. The Key guidelines for successful Quality
Circles  include:
- participation is voluntary
- management must be supportive for the continued operation of effective
- employees are empowered
- training is an integral part of the programme
- members work as a team to identify and solve problems
has suggested that there are ten ingredients for a successful team:
- clarity in team goals
an improvement plan
- an agreed mission, purpose and goals.
clearly defined roles
- schedules, milestones and deliverables.
- an understanding of duties and responsibilities.
beneficial team behaviours
- clarity of speech, active listening and shared information.
well-defined decision procedures
- skills and practices for effective meetings and discussions/decisions.
- evidence-based decisions with consensus on important issues.
established ground rules
- everyone should participate/contribute and share commitment to the
awareness of the group process
- known limits to acceptable and unacceptable behaviour.
use of the scientific approach
- sensitivity to non-verbal communication and understanding of group
- structured problem-solving processes.
Ho  defines fifteen stages for the implementation of successful Quality
- management briefing to raise awareness of the QC process
- the feasibility of QC is analysed
- formation of a steering committee
- co-ordinator and in-house instructor are selected
- potential areas for initial QCs are selected
- QC presentations made to appropriate first-line supervisors
- co-ordinators and middle management trained on the process and their
- supervisors volunteer and receive training
- newly trained supervisors make QC presentations to the employees
- employees volunteer to join the circle and receive training
- the circle is formed and begins its work
- additional circles form as interest broadens
- circles discuss and systematically solve problems
- management ensure rapid implementation once solutions have been accepted
by the QC
- management ensure appropriate and proper recognition of the QC team
and suggests the following code of conduct for discussion within the QC:
- criticise ideas, not people
- the only stupid question is the one that is not asked
- everyone in the team is responsible for team progress
- everyone should be open to the ideas of others
- pay, terms of employment and other negotiable items are specifically
excluded from discussion
Where the company and employee organisations (unions) agree, employee
participation and empowerment can convert QC teams into Self-Managed Teams (SMT). Donovan 
suggests that the process to achieve this is:
- create a work unit responsible for an entire task including establishing
standards and customer relations
- establish specific measures of output from the work team with feedback
- systematic study of workflow functions and variances leading to
- transfer of internal management and co-ordination from management to the
- definition of the boundaries of the allocated management task
- establishing access to the required information
- establishing support systems (training, career progression, access to
management, rewards and payments)
Kaizen (a culture of continuous improvement)
Many of the greatest opportunities for improving the performance of an
organisation lie at the interfaces between individual defined functions. A
process perspective enhances understanding of the role of the sub-process within
the greater system. Many small and gradual improvements, combined with
occasional large and rapid improvements and breakthroughs combine to produce
continuous improvement. Such improvements may well arise from significant
simplification of the processes undertaken. Deming ("improve constantly
and forever") focussed on understanding suppliers and customers as crucial to
planning for quality. Ho  states that "by eliminating various root
causes of problems in the process, variation decreases, thus increasing the
quality of the output" and cites the Deming
cycle as an elementary tool to achieve such change.
The kaizen strategy has been called "the single most important concept in
Japanese management - the key to Japanese competitive success" . It is
a philosophy which subsumes all business activities and everyone in the
organisation. If the quality of the people is improved (perhaps by
involvement, training and education rather than by replacement), improvement of
the quality of the products will follow. Any activity directed towards
improvement is included within kaizen, including:
- improved working standards through gradual improvements
- using a systems approach and problem solving tools to realise the required
- devolving responsibility for maintaining standards to the worker whilst
management seeks to improve standards
- planned maintenance
- traditional quality control systems
- automation, robotics and advanced technology
- just-in-time methodologies
- employee suggestion schemes
The Kaizen Institute [1, p.410] suggest
that continual improvement may arise by:
- discarding conventional ideas
- considering how something might be done, not why it cannot be done
- not seeking perfection
- not making excuses, but questioning current practices
- seeking the wisdom of ten people rather than the knowledge of one person.
Do note that continual improvement implies forever: ever increasing pressure
from customers and the market place drives all companies and if the competition
are continuing to make improvements, then over time your company can fall from
its leading position.
Poka-Yoke (mistake-proofing) and Zero Quality Control (ZQC) 
Human beings tend to make mistakes and errors can thus inadvertently arise
due to [1, p.617]:
- forgetfulness through lack of concentration
- misunderstanding due to lack of familiarity
- poor identification associated with lack of proper attention
- lack of experience
- delays in judgement in automated process
- equipment malfunctions
In the early 1960s Shigeo Shingo introduced the concept of Poka-Yoke through
the introduction of mechanical devices into assembly operations at Yamada
Electric such that parts were prevented from being assembled incorrectly.
The key to the process is to stop the process whenever a defect occurs,
define the cause and prevent recurrence. Once the errors leading to
defects have been identified, they can be addressed. Poka-Yoke is
especially useful in assembly work and in working practices in the service
sector. Where Poka-Yoke is fully implemented, statistical process control
is not needed for zero-defect operations.
Many applications are deceptively simple, but have required a creative
solution to a potential problem. Examples of Poka-Yoke solutions to common
- 3.5-inch computer discs and secure digital memory cards where one corner
is angled to prevent inverted insertion of the item
.. this in turn is derived from the Hollerith punched card (which in-turn drew
on Babbage and Jacquard's loom) 
- a clear template overprinted with the keyboard letters for checking the
correct positioning of the individual keys
- the warning message displayed if a computer program is closed without
recent changes having been saved
- on-line computer forms which cannot be submitted with crucial fields left
- redesigned screws with finite length slots (i.e. not full width) matched
to the screwdriver to prevent scratching when screwdrivers slip
- different tube diameters for blood- and food-transfusion in hospitals
- trays for surgical implements with specific indentations for each tool so
nothing is knowingly left inside the patient
- the "dead-mans handle" on trains and other power tools so that operation
is dependent on a person being present
- scoops in fast-food outlets that accurately deliver the required portion
of french fries
- prompts to greet and question the customer on the check-out display in
- paper strips around towels in hotels to identify which linen need to be
as well as
Grout's on-line everyday examples of Poka-Yoke.
- J Evans and W Lindsay, The Management and Control of Quality - Fifth
Edition, South-Western/Thomson Learning, Cincinnati OH, 2001. ISBN
0-324-06680-5. PU CSH Library.
- PR Scholtes et al, The Team Handbook - How To Use Teams To Improve
Quality, Joiner Associates Inc, Madison WI, 1988. second edition, 1998: ISBN 1-88473-111-2. PU CSH Library.
- SKM Ho, Operations and Quality Management,
International Thomson Business, 1999. ISBN 1-86152-398-x. PU CSH Library.
- JM Donovan, Self-Managing Work Teams: Extending The Quality Circle
Concept, Quality Circles Journal, March 1986, 9(3), 15-20.
- M Imai, Kaizen - The Key To Japan's Competitive Success,
McGraw-Hill, New York, 1986. PU CSH Library.
- S Shingo, Zero Quality Control: Source Inspection and the Poka-Yoke
System, Productivity Press Inc, 1 May 1986. ISBN 0-915-29907-0. PU CSH Library.
- J Essinger, Jacquard’s Web – how a hand loom led to the birth of the information age, Oxford University Press, Oxford, 2004. ISBN 0-19-280577-0.
URLs for Quality Circles, Kaizen and Poka-Yoke (checked as live on 26 August 2004):
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Created by John Summerscales on 27 November 2004 and updated on
24-Jul-2014 12:26. Terms and conditions. Errors and omissions. Corrections.