What is the definition of "key quality characteristic"?
A measurable characteristic of a product that greatly impacts customer satisfaction. Key quality characteristics are the focus of SPC efforts.

Learn more about key quality characteristic in the class SPC Overview 210 below.

Quality Training

Class Information
Tooling U classes are offered at the beginner, intermediate, and advanced levels. The typical class consists of 12 to 25 lessons and will take approximately one hour to complete.
Class Name:SPC Overview 210
Description:This class describes the main concepts of statistical process control and explains how to recognize processes that are affected by special causes. Includes an Interactive Lab.
Prerequisites: 800220  900100 
Number of Lessons:16
Language:English, Spanish, Chinese

Go to Catalog

Below are all the competencies and job programs that contain the class SPC Overview 210. Job programs are our traditional class lists organized according to common job functions. Competencies are our latest job-specific curricula that help tie online learning to practical, hands-on tasks.

Click on any title to view its details.

Class Outline
  • Objectives
  • The Definition of Quality
  • Key Quality Characteristics
  • Definition of SPC
  • Common Causes and Special Causes
  • Control Charts
  • Control Limits
  • The X Bar Chart
  • Average Sample Size
  • The R Chart
  • The P Chart
  • Process Capability vs. Process Control
  • The In-Control Process
  • The Out-of-Control Process
  • Process Improvement
  • Summary
Class Objectives
  • Describe how customer demands relate to product specifications.
  • Define key quality characteristic.
  • Define statistical process control.
  • Distinguish between common causes and special causes.
  • Describe the purpose of a control chart.
  • Describe the purpose of control limits.
  • Describe the general appearance of an chart.
  • Distinguish between the effects of variation on individual measurements and sample averages.
  • Describe the general appearance of an R chart.
  • Describe the general appearance of a P chart.
  • Distinguish between process capability and process control.
  • Identify a process that is in control.
  • Identify signs that a process may be out of control.
  • Describe how statistical process control leads to process improvement.

Class Vocabulary

Vocabulary TermDefinition
attribute data Data that represents the absence or presence of characteristics. Go/no-go gaging or the presence/absence of a component yield attribute data.
bell-shaped curve A graph of variable data characterized by a high center, tapered sides, and bell-flared edges. A bell-shaped curve reflects conditions that exhibit natural variation.
centerline The horizontal line on a control chart that represents the average for a process.
common cause A source of variation that is normal and expected. Common causes are predictable over time and yield a normal distribution.
control chart A graph used during SPC efforts that charts data and provides a picture of how a process is performing over time.
control limit A horizontal line on a control chart that represents a boundary for a process. If the process strays beyond a control limit, it is out of control.
external customer An organization or individual that receives a product or service from the company.
grand average The average of sample averages. The grand average is the centerline on an X bar chart.
internal customer A department or individual within the company that relies on others to satisfy the external customer.
key quality characteristic A measurable characteristic of a product that greatly impacts customer satisfaction. Key quality characteristics are the focus of SPC efforts.
lower control limit A control limit indicating the boundary for the minimum permissible values.
micrometer A U-shaped measuring instrument with a threaded spindle that slowly advances toward a small anvil. Micrometers are available in numerous types for measuring assorted dimensions and features.
natural variation Variation resulting from sources that are normal and expected. Natural variation is predictable over time.
normal distribution Variable data that clusters about an average and is symmetrical. When graphed, a normal distribution appears as a bell-shaped curve. In-control processes yield a normal distribution.
P chart The control chart that tracks the percentage of nonconforming items. A P chart is used with attribute data.
process capability The total range of variation within a process, including common and special causes.
process control The range of variation within a process after special causes have been eliminated.
processes A set of activities that uses resources to transform inputs into outputs. Essentially, a process describes the way "things get done."
quality The satisfaction of customer requirements. Quality products conform to specifications, are free of defects, and meet the requirements of its anticipated use.
R chart The control chart that tracks sample ranges over time. An R chart is used with variable data.
sigma A unit of standard deviation indicating the degree of spread within a set of measurements.
special cause A source of variation that causes a fundamental change in a process. Special causes distort a normal distribution and are undesirable.
statistical process control The use of statistics and control charts to measure key quality characteristics and control how the related process behaves. SPC separates special causes of variation from common causes.
statistics The science of collecting, summarizing, and analyzing numerical data. Statistics makes it possible to predict the likelihood of events.
tolerance A blueprint specification indicating an unwanted but acceptable deviation from a given dimension.
unnatural variation Variation resulting from one or more sources that involve a fundamental change in a process. Unnatural variation is undesirable.
upper control limit A control limit indicating the boundary for the maximum permissible values.
variable data Data that contains a range of quantities. Most measurements yield variable data.
variation A difference between two or more similar things.