17.4 Maintenance Strategies
Maintenance strategies form the backbone of effective asset management, directly influencing operational efficiency, equipment reliability, and cost control. Selecting the appropriate mix of strategies enables organizations to extend asset life, reduce unplanned downtime, and optimize resource utilization.
This section outlines the primary maintenance strategies commonly used across industries (Fiix Software, 2023).
1. Reactive Maintenance (Run-to-Failure / Corrective Maintenance)
Reactive maintenance involves taking corrective action only after equipment has failed or a defect has been detected. Often referred to as run-to-failure, this approach is typically reserved for non-critical assets where failure does not significantly impact safety, operations, or costs.
Examples: Light bulbs, inexpensive motors, or non-essential tools.
Key Characteristics:
- Minimal planning or upfront investment.
- Repairs or replacements occur only after failure.
| Advantages | Disadvantages |
| Simple to implement with low administrative burden. | High unpredictability and risk of costly emergency repairs. |
| Lower short-term costs due to maintenance being performed only when needed. | Increased downtime and potential for secondary damage. |
| Unsuitable for critical systems due to safety and operational risks. |
2. Preventive Maintenance (PM)
Preventive maintenance involves performing scheduled inspections, servicing, and part replacements at predetermined intervals—either time-based (e.g., monthly) or usage-based (e.g., after 1,000 operating hours). The goal is to prevent failures before they occur.
This strategy is ideal for equipment with predictable failure patterns or those subject to regulatory compliance (e.g., elevators, fire alarms).
Key Characteristics:
- Maintenance is performed regardless of the current equipment condition.
- Focuses on early detection of wear and tear.
| Advantages | Disadvantages |
| Reduces breakdowns and unplanned downtime. | May result in unnecessary maintenance or over-servicing. |
| Increases asset reliability, efficiency, and lifespan. | Requires careful scheduling and documentation. |
| Enhances safety by addressing issues before escalation. | Does not eliminate all failures. |
3. Predictive Maintenance (PdM)
Predictive maintenance uses real-time monitoring, data analytics, and diagnostic tools (e.g., vibration analysis, thermal imaging, sensor data) to predict when equipment is likely to fail. Maintenance is then performed only when needed, based on actual asset condition.
This strategy is best suited for high-value or complex assets where failures are costly or disruptive (e.g., turbines, production lines).
Key Characteristics:
- Condition-based rather than schedule-based.
- Requires investment in monitoring technologies and skilled personnel.
| Advantages | Disadvantages |
| Minimizes downtime and avoids unnecessary maintenance. | High initial cost for sensors, software, and analytics. |
| Maximizes asset lifespan and operational efficiency. | Requires skilled staff to interpret data accurately. |
| Enables precise planning for parts and labour. | It may not be feasible for all asset types. |
Condition-Based Maintenance (CBM)
A specialized form of predictive maintenance, CBM triggers maintenance actions only when specific measured conditions (e.g., temperature, vibration, pressure) exceed predefined thresholds. It is highly responsive and tailored to the real-time state of the asset.
Example: A pump is serviced only when vibration levels exceed safe limits, as detected by sensors.
Strategic Integration
In practice, organizations often adopt a hybrid approach, combining multiple strategies based on asset criticality, cost, and operational context. For example:
- Reactive maintenance for low-risk, low-cost assets.
- Preventive maintenance for moderately critical systems.
- Predictive/condition-based maintenance for high-value or safety-critical equipment.
The following video gives a comparative review of the above maintenance strategies.
Video: “3 Maintenance Strategies: Which Works Best?” by Asset Insights [3:42] is licensed under the Standard YouTube License.Transcript and closed captions available on YouTube.
Aligning Maintenance with Reliability
As established throughout this chapter, maintenance is a key enabler of reliability. The effectiveness of maintenance activities depends on how well they align with the principles of reliability engineering—namely, minimizing failure, maximizing uptime, and optimizing asset performance over time.
While various maintenance strategies offer different levels of success, two advanced approaches- Reliability-Centred Maintenance (RCM) and Risk-Based Maintenance (RBM) are particularly effective in aligning maintenance with reliability goals.
1. Reliability-Centred Maintenance (RCM)
RCM is a comprehensive strategy that integrates multiple maintenance approaches to optimize asset performance based on criticality, failure modes, and operational context. It uses Failure Mode and Effects Analysis (FMEA) to identify the most appropriate maintenance method—reactive, preventive, or predictive—for each asset.
RCM is especially valuable in industries with diverse and mission-critical assets, such as utilities, pharmaceuticals, and food processing, where reliability is non-negotiable.
Key Features:
- Tailors maintenance to asset-specific risks and functions.
- Focuses on maximizing reliability while controlling costs.
- Encourages continuous improvement through feedback loops.
| Advantages | Disadvantages |
| Highly customized, improving asset availability and safety. | Requires detailed analysis and data collection. |
| Reduces unnecessary maintenance and optimizes resource use. | Higher upfront investment in training and system design. |
| Supports long-term reliability and cost-efficiency. | Complex to implement, especially in large organizations. |
The following video provides a brief review of reliability-centred maintenance
Video: “Chapter 1 – Introduction to Reliability Centered Maintenance” by Get Insight [6:38] is licensed under the Standard YouTube License.Transcript and closed captions available on YouTube.
2. Risk-Based Maintenance (RBM)
RBM prioritizes maintenance activities based on the risk associated with asset failure, considering both the likelihood and consequences of failure. Assets are ranked using risk assessment tools (e.g., risk matrices), and maintenance schedules are adjusted accordingly.
This strategy is particularly effective in safety-critical or environmentally sensitive environments, such as nuclear power plants, chemical processing, or aviation.
Key Features:
- Focuses resources on high-risk assets.
- Enhances safety, compliance, and operational resilience.
- Requires ongoing reassessment as conditions evolve.
| Advantages | Disadvantages |
| Improves risk management by targeting critical assets. | Depends on accurate risk and consequence analysis. |
| Enhances safety and regulatory compliance. | Requires continuous monitoring and reassessment. |
| Optimizes resource allocation. | May overlook low-risk assets that still impact performance. |
Comparison of Maintenance Strategies
| Strategy | Description | Key Benefits | Best Used For |
| Reactive / Corrective | Fix after failure | Simple, low upfront cost | Non-critical, low-risk assets |
| Preventive | Scheduled routine maintenance | Reduces failures, predictable costs | Assets with predictable wear |
| Predictive | Data-driven, real-time monitoring | Optimized timing, minimized downtime | High-value, critical equipment |
| Condition-Based | Based on asset condition thresholds | Just-in-time, efficient | Assets with variable operating conditions |
| Reliability-Centered | Combined, optimized methods | Risk-based, resource-efficient | Complex, critical facilities |
| Risk-Based | Prioritized by risk impact | Focuses on critical assets | Risk-sensitive operations |
