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Six Sigma - Know All You Wanted to Know!
Everyone is talking about it; it's on every manager's mind and it's definitely taking some
people places. Read on to know all about Six Sigma.
Six Sigma is a method that employs statistical analysis to reduce or even eliminate defects,
defined as "unacceptable deviation from the mean", in manufacturing and service related
processes. It stands for Six Standard Deviations (sigma being the Greek alphabet repre-
senting standard deviation). Broadly, Six Sigma has three aspects: the metric, the method-
ology and its philosophy. Together, they help reduce the defects per million opportunities
(DPMO) to 3.4, which is the Six Sigma benchmark.
The methodology of Six Sigma comprises the DMAIC and the DMADV approaches. The
former is what you need if you already have your system in place. On the other hand, if
you are planning a new setup, then DMADV will deliver the best results.
DMAIC expects you to Define goals consistent with your strategies and customer needs,
Measure the process and collect requisite data, Analyze the opportunities looking for rela-
tionships between factors, Improve the process using techniques like 'Design of Experi-
ments' and Control performance by setting up mechanisms to limit the variance before it
results in defects.
Apart from Defining goals, Measuring variables critical to quality, Analyzing and looking
for alternatives if any, DMADV requires you to Design the production process and Verify
it. A related and emerging principle is the Design for Six Sigma (DFSS) which seeks to find
what customers and the business need before designing a process to suit the same. To get a
larger picture, refer to "Six Sigma Study Guide" by Bryan Dodson available at
Extensive training of concerned personnel is crucial for effective implementation. The key
roles identified by Six Sigma include the following:
Executive leadership comprising the CEOs and the top management who are trained to
identify projects for Six Sigma implementation.
Champions responsible for implementation in an integrated manner.
Master black belts who dedicate all their time to Six Sigma. Apart from deal-
ing with the statistics, they ensure deployment across functions and depart-
ments.
Black belts work under the guidance of the masters and restrict their focus to
specific projects.
Green belts are the employees who carry out implementation of Six Sigma
along with their other responsibilities.
The certification for these levels is available at different institutes as well as
online. Training a majority of your staff to accommodate Six Sigma in their
professional lives will come at a price, however the benefits reaped later will
more than compensate.
Six Sigma could be contrasted with its older counterparts in quality control;
TQM, Lean and Kaizen to name a few.TQM stands for Total Quality Man-
agement and is quite comprehensive in its approach. While it does concen-
trate on removing errors in processes, it also calls for a culture change at all
levels of employees. Six Sigma is often claimed to be less bureaucratic than
TQM. Kaizen was developed by Toyota and is a mechanism to bring about
small but incremental changes over a period of time, as opposed to Six Sigma
which focuses on developing breakthrough solutions. Lean manufacturing is
a management technique that focuses on removing seven types of wastage to
improve efficiency. Lean Six Sigma is another technique which combines
both the principles to give quality control a broader applicability. To learn
more, you can get hold of the book by Michael George titled "Lean Six Sigma
for Service: How to use Lean speed and Six Sigma quality to improve ser-
vices and transactions" available at or you could try for all you need on Lean
Six Sigma.
Originating in Motorola, several managers claim that Six Sigma has brought
about drastic reductions in their costs. Its application is extending to fields
like health care, banking and even the military. While Six Sigma is undoubt-
edly a path breaking development, it does not do away with other quality
control measures. A combination of the several techniques available is opti-
mal.

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6283177 lean-six-sigma

  • 1. Six Sigma - Know All You Wanted to Know! Everyone is talking about it; it's on every manager's mind and it's definitely taking some people places. Read on to know all about Six Sigma. Six Sigma is a method that employs statistical analysis to reduce or even eliminate defects, defined as "unacceptable deviation from the mean", in manufacturing and service related processes. It stands for Six Standard Deviations (sigma being the Greek alphabet repre- senting standard deviation). Broadly, Six Sigma has three aspects: the metric, the method- ology and its philosophy. Together, they help reduce the defects per million opportunities (DPMO) to 3.4, which is the Six Sigma benchmark. The methodology of Six Sigma comprises the DMAIC and the DMADV approaches. The former is what you need if you already have your system in place. On the other hand, if you are planning a new setup, then DMADV will deliver the best results. DMAIC expects you to Define goals consistent with your strategies and customer needs, Measure the process and collect requisite data, Analyze the opportunities looking for rela- tionships between factors, Improve the process using techniques like 'Design of Experi- ments' and Control performance by setting up mechanisms to limit the variance before it results in defects. Apart from Defining goals, Measuring variables critical to quality, Analyzing and looking for alternatives if any, DMADV requires you to Design the production process and Verify it. A related and emerging principle is the Design for Six Sigma (DFSS) which seeks to find what customers and the business need before designing a process to suit the same. To get a larger picture, refer to "Six Sigma Study Guide" by Bryan Dodson available at Extensive training of concerned personnel is crucial for effective implementation. The key roles identified by Six Sigma include the following: Executive leadership comprising the CEOs and the top management who are trained to identify projects for Six Sigma implementation.
  • 2. Champions responsible for implementation in an integrated manner. Master black belts who dedicate all their time to Six Sigma. Apart from deal- ing with the statistics, they ensure deployment across functions and depart- ments. Black belts work under the guidance of the masters and restrict their focus to specific projects. Green belts are the employees who carry out implementation of Six Sigma along with their other responsibilities. The certification for these levels is available at different institutes as well as online. Training a majority of your staff to accommodate Six Sigma in their professional lives will come at a price, however the benefits reaped later will more than compensate. Six Sigma could be contrasted with its older counterparts in quality control; TQM, Lean and Kaizen to name a few.TQM stands for Total Quality Man- agement and is quite comprehensive in its approach. While it does concen- trate on removing errors in processes, it also calls for a culture change at all levels of employees. Six Sigma is often claimed to be less bureaucratic than TQM. Kaizen was developed by Toyota and is a mechanism to bring about small but incremental changes over a period of time, as opposed to Six Sigma which focuses on developing breakthrough solutions. Lean manufacturing is a management technique that focuses on removing seven types of wastage to improve efficiency. Lean Six Sigma is another technique which combines both the principles to give quality control a broader applicability. To learn more, you can get hold of the book by Michael George titled "Lean Six Sigma for Service: How to use Lean speed and Six Sigma quality to improve ser- vices and transactions" available at or you could try for all you need on Lean Six Sigma. Originating in Motorola, several managers claim that Six Sigma has brought about drastic reductions in their costs. Its application is extending to fields like health care, banking and even the military. While Six Sigma is undoubt- edly a path breaking development, it does not do away with other quality control measures. A combination of the several techniques available is opti- mal.