The terms below are those used in this book for which alternative definitions may be provided in ISO 9000. For other terms the reader is directed to ISO 9000.

5 Why s These typically refers to the practice of asking, five times, why a failure has occurred in order to get to the root cause. For example:

1. Why did the machine stop? Because there was an overload and the fuse blew.

2. Why was there an overload? Because the bearing was not sufficiently lubricated.

3. Why was the bearing not lubricated sufficiently? Because the lubrication pump was not pumping.

4. Why was the lubrication pump not pumping? Because the pump shaft was worn.

5. Why was the pump shaft worn? Because there was no seal around the shaft and metal debris penetrated the gap.

6 M s These are the six words that are used to title the arms in a fishbone diagram. The words vary but the most commonly used M s are:

1. machines;

2. methods;

3. materials;

4. measurements;

5. milieu (surrounding environment);

6. manpower.

One could also add money and management.

8 D s A problem-solving method that is structured into eight disciplined steps. The eight basic steps are:

1. establish a team,

2. describe the problem,

3. develop interim containment,

4. define and verify root cause,

5. choose permanent corrective action,

6. implement corrective action,

7. prevent recurrence,

8. recognize and reward the contributors.

Note: Some of the terms are not...