First Edition Dated September, 2000 27
are achieved through a combination of teaming, documentation, training, and
measurement. Examples of methods to achieve standard processes are
visual controls, product/process value stream analysis and mapping, setup
reduction activities/procedures, optimizing manufacturing flows, obtaining
input and agreement from cross-functional team members, and using
“lessons learned” on similar products/processes.
Benefits of standard processes include less variation among employees, time
savings, reduction in rework and scrap, better communication and the ability
to readily detect abnormal events. Once verified by performance data, a
standard process can be considered a reliable process.
Mistake Proofing
Mistake proofing is perhaps one of the simplest and most commonly used
methods for controlling variation. The goal of mistake proofing is to make
variation impossible to occur, usually through physical means. Examples of
mistake proofing include color coding of parts and tools, tabs and slots on
mating components, and other controls on size and orientation.
Benefits of mistake proofing include fewer rejections, higher quality and
improved customer satisfaction. In addition, costs can be lowered through
reduction in skills training, rework and scrap.
Summary
Key characteristics should be produced by a standard process and be
controlled by a method that can ensure the product is close to target, is
stable, has minimum variation, and meets the capability requirements.
Section 4.2.3 The selected variation control technique shall
be documented on the AQS Control Plan, or equivalent.
For Boeing defined key characteristics, the requirement to
control and reduce variation may be subject to an
agreement as documented on the AQS Control Plan, or
equivalent.
The AQS Control Plan provides for the documentation of the method of
variation control for each key characteristic identified. If other methods are
used, they should be noted on the AQS Control Plan and the results
recorded.
