AS9100C 2009 Plain English Definitions

We have translated the ISO 9000 2005 and AS9100C quality management
definitions into plain English in order to make them easier to understand.
Our plain English definitions are primarily based on the formal definitions
found in the ISO 9000 standard and on the definitions added by AS9100C.

Critical Item

Items are critical if they have a major impact on the realization
and use of the product. Items are critical if they have a significant
effect on the safety, performance, form, fit, function, producibility,
or service life of the product. Critical items require specific actions
to ensure that they are adequately managed.

Examples of critical items include key characteristics, parts,
functions, processes, and software. They include mission
critical items, safety critical items, and fracture critical items

Key Characteristic

A key characteristic is a feature or attribute that has a significant
impact when it varies. Whenever a key characteristic varies, it has an
important effect on the performance, form, fit, function, producibility,
or service life of the product. Therefore, key characteristic variations
must be controlled.


A risk is an undesirable situation or circumstance that has
two characteristics: it is both likely to occur and likely to cause
negative consequences

The concept of risk is always future oriented. It worries about
the impact that undesirable circumstances or situations could
have in the future.

Special Requirement

A special requirement is a requirement that may be especially difficult
to achieve. Special requirements may be difficult to achieve because
they force you to operate at the limit of your organizationís technical
or process capability or at the limit of your industryís capability.

Either you or your customer may decide that a requirement is special.
In order to figure out whether or not a requirement is special, consider
the complexity and maturity of your product or process and your
organizationís past experience.

Since there is a risk that your organization may not be  able to
meet a special requirement, youíre expected to include it in your
risk management process.

NOTE: Critical items, special requirements, and key characteristics are new
interrelated concepts. Special requirements force you to operate at or near
the limit of your organizationís capability. Therefore, they tend to be difficult
to achieve. In order to meet these difficult requirements you may need to
carefully manage critical items. And if such items tend to vary, you may
also need to treat them as key characteristics in order to control them.

Additional Quality Management Definitions


Introduction to AS9100C Standard

Overview of Quality Management Standard

AS9100C Standard Translated into Plain English

How to Upgrade to the new AS9100C:2009 Standard

Aerospace Quality Management Gap Analysis Tool

Aerospace Quality Management Audit Program

Home Page

Our Libraries

A to Z Index

Our Customers

How to Order

Our Products

Our Prices

Our Guarantee

Praxiom Research Group Limited       780-461-4514

Updated on May 17, 2016. First published on August 31, 2009.

Legal Restrictions on the Use of this Page
Thank you for visiting this webpage. You are welcome to view our material as often as
you wish, free of charge. And as long as you keep intact all copyright notices, you are also
welcome to print or make one copy of this page for your own personal, noncommercial,
home use. But, you are not legally authorized to print or produce additional copies or to
copy and paste any of our material onto another web site or to republish it in any way.

Copyright © 2009 - 2016 by Praxiom Research Group Limited. All Rights Reserved.

Praxiom Research Group Limited