Preventive Maintenance (or Preventative Maintenance) is a process in which we can prevent major failures of equipment by scheduling various activities to keep that equipment in peak condition.  Here are five productivity gains that can be achieved if you adopt a Preventive Maintenance programme in your business or in your customer’s business.

1. Plant Safety.  To avoid injuries to Operators it is important that the equipment is maintained to the highest standard.  Regularly scheduled preventive maintenance not only confirms that the equipment is working properly, but also avoids emergency situations and outages, which, in terms of safety concerns, may be too late.
2. Efficiency.  As normal wear and tear can result in diminishing efficiency a Preventive Maintenance plan ensures that the effectiveness and life of your equipment is conserved. 
3. Immediate Savings.  For many reasons, money can be saved when conducting preventive vs. emergency maintenance. Examples are:- (1) Preventive Maintenance costs less to facilitate than a large repair or replacement, and (2) Knowing when a scheduled shutdown will occur allows you to staff accordingly.
4. Long-term Savings.  Preventive Maintenance allows your equipment to run at higher capacities for longer, allowing you to get the most from your investments.
5. Time Savings.  In general Preventive Maintenance procedures take less time to complete than emergency repairs and replacements. Also, as you can plan for the equipment being unavailable during maintenance, you can avoid an outage when you need the machine the most.

Evolution of Maintenance Systems

Early Preventive Maintenance systems were manual in nature. These required the use of preventive maintenance forms and service sheets.  Initially these related to maintenance events derived from actual historical breakdowns which provided a Mean Time Between Failure (MTBF) frequency.   This provided a frequency for creating a 'Planned' Maintenance Event.    However, with the introduction of computer technology the use of Preventive Maintenance software became the preferred way of managing this functional area.  Evolution of this computerisation has extended the scope of a Preventive Maintenance process beyond simply 'Planned' Maintenance and can now include:-

Planned Event - These are Maintenance Events scheduled at a pre-defined date.
Recurring Event - These are Events based on a regular recurring Frequency.  This Frequency can be 

• Number of days from completion of previous event
• Day of the Week
• Day of the Month (every 1st, 2nd, 3rd, or 4th Week)
• Month of the Year (day number in the Month)

Predictive Event – Based upon predictions derived from Actual usage rather than time.  (For example: 30000Km or 12 Months whichever comes first; copies; cycles).
One-Off Event – Usually the first ‘Post Sales’ service. (For example an initial 500Km service after the sale of a new Car)
Breakdown Events – A Service carried out on an Asset as the result of a Breakdown.

Today Maintenance systems also include activities outside the original scope of simply maintaining Company 'Plant'.  Examples are:-

• Routine Building Inspections
• Regular Safety Equipment checks
• Customer Equipment Servicing
• etc.  

To adequately cover this increased scope maintenance computer programs were enhanced to include:

• Recording of current usage of equipment in 'Real Time' (I.e. auto updating via the Internet).  This not only provides information for the 'Predictive Service Event’ but also provides information for immediate usage billing.
• Multiple Events per Item of Equipment.  A good example is a motor vehicle which could have a maintenance event with "Every 6 months or 6000Km whichever comes first" and another of "Every 12 months or 12000Km whichever comes first"
• 'Grouping' of Customer Equipment (Location or Service Route) and filtered by planned date so that they can be regularly serviced by Field Maintenance Staff.