From Elsmar Cove Quality Assurance and Business Standards Wiki
Preventive Maintenance - Maintaining scheduled up-keep and improvement to equipment so equipment can theoretically improve with age.
The combination of all actions in a plant to prevent equpment / machine failures and to detect failures early. The two parts of preventive maintenance are:
1. Condition monitoring (actions that detect failures)
2. Maintenance (actions that prevent failures).
Examples of condition monitoring are all inspections: look, listen, feel, smell, vibration analysis, Amp readings, infrared, ultrasonics, and oil analysis.
Examples of maintenance are: lubrication, alignment, balancing, operating procedures, cleaning, adjustment, and much more. Condition Monitoring is often looked upon as mostly being vibration analysis.