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ОглавлениеI have not failed. I have found 10,000 ways that won’t work.
—THOMAS EDISON
After reading this chapter, you will be able to understand:
• What best practices are and why we care
• What best practices have to do with maintenance and reliability
• Key maintenance and reliability (M&R) and asset management (AM) terms and benchmark examples
Also, you will be able to assess your knowledge about the fundamentals of maintenance, reliability, and asset management best practices by taking a test.
Introduction: What Is a Best Practice?
The notion of a best practice is not new. Frederick Taylor, the father of modern management, said nearly 100 years ago, “Among the various methods and implements used in each element of each trade, there is always one method and one implement which is quicker and better than any of the rest.” In recent times, this viewpoint has come to be known as the “one best way” or “best practice.”
“Best practice” is an idea that asserts there is a technique, method,or process that is more effective at delivering the desired outcome than any other technique, method, or process. With this technique, a project or an activity such as maintenance can be completed with fewer problems and unforeseen complications. Simply, a technique, method, or process may be deemed a best practice when it produces superior results.
A best practice is typically a documented practice used by the most respected, competitive, and profitable organizations. When implemented appropriately, it should improve performance and efficiency in a specific area. We must understand that best practice is a relative term. To some, it may be a routine or a standard practice; to others, it may be a best practice because the current practice or method is not effective in producing the desired results.
History is filled with examples of people who were unwilling to accept or adopt the industry standard as the best way to do anything. The enormous technological changes since the Industrial Revolution bear witness to this fact. For example, at one time horses were considered the best form of transportation, even after “horseless carriages”were invented. Today, most people drive a gasoline (petrol), electric, or hybrid vehicle—all improvements on the original horseless carriage. In turn, concerns over oil costs, supplies, and global warming are driving the next group of transportation improvements.
In the 1968 Summer Olympics, a young athlete named Dick Fosbury revolutionized the high-jumping technique. Using an approach that became known as the Fosbury Flop, he won the gold medal by going over the bar back-first instead of head-first. Had he relied on “standard practice,” as did all his fellow competitors, he probably would not have won the event. Instead, by ignoring standard practice, he raised the performance bar—literally—for everyone. The purpose of any standard is to provide a kind of reference. Therefore, that standard must be “What is possible?” and not “What is somebody else doing?”
In real-world applications, a best practice is a very useful concept. Despite the need to improve processes with changing times, a best practice is considered by some simply to be a business buzzword used to describe the process of developing and following a standard way of doing activities that any organization can use or implement to get better results. Implementing best practices in the area of maintenance, reliability, and asset management can help an organization to:
• Increase output with the same set of assets
• Reduce the need for capital replacements
• Reduce maintenance cost per unit
• Reduce the total cost per unit of output
• Improve performance—cost, productivity, and safety
• Reduce the total cost of ownership (TCO)
• Increase competitiveness
• Increase market share
A best practice tends to spread throughout an industry after success has been demonstrated. However, demonstrated best practices could be slow to implement, even within an organization. According to the American Productivity and Quality Center, the three main barriers to the adoption of a best practice are a lack of:
1. Knowledge about current best practices
2. Motivation to make changes for their adoption
3. Knowledge and skills required to do so
The objective of this book is to provide knowledge of best practices in the areas of maintenance, reliability, and asset management. Cost-effectively implementing and sustaining best practices requires a culture of reliability excellence that is a journey and takes time. In later chapters, we will discuss what we can do to eliminate barriers and create a sustainable reliability culture in an organization.
Asset
A component or device, software, or a system that has potential or actual value to the organization. Value can be tangible or intangible, financial or nonfinancial.
Asset Management
An organizational process that maximizes value from an asset during its life.
Benchmark
A standard measurement or reference that forms the basis for comparison. This performance level is recognized as the standard of excellence for a specific business process.
Best Practice
A technique, method, or process that is more effective at delivering the desired outcome than any other technique, method, or process. It is a documented practice used by the most respected, competitive, and profitable organizations. This practice usually becomes a benchmark.
Maintenance
The act of maintaining or the work of keeping an asset in proper operating condition. Also called capacity assurance.
Organization
A group of people (or an individual) that has its own functions with responsibilities and relationships to achieve its objectives. The organization includes, but is not limited to, sole trader, company, corporation, enterprise, department, plant or factory, partnership, charity or institution, or part or combination thereof.
Reliability
The probability that an asset or item will perform its required functions for a specific period under stated conditions. It is usually expressed as a percentage and calculated using mean time between failures (MTBF).
What Do Best Practices Have to Do with Maintenance and Reliability?
In any organization, assets are needed to produce products or provide services. An item or asset, as defined here, could be an electrical/electronic or mechanical hardware component or device, a building, a software product, or a manufacturing system or process.
A well-designed, robust M&R program is required to ensure that assets are available and cost-effectively performing to their designed capacity when needed in an organization. The performance of an asset is based on three factors (see Figure 1.1):
1. Inherent reliability—how it was designed
2. Operating environment—how it will be operated
3. Maintenance plan—how it will be maintained
FIGURE 1.1 Asset Performance
Usually, assets are designed with a certain level of reliability. This designed-in (or built-in) reliability—inherent reliability, the first factor in the list above—is the result of the individual components’ reliability and the way they are configured. We cannot change or improve the reliability of an asset after it has been installed unless we replace or modify it with better and improved components (with the exception of redesigning it).
The second factor, the asset’s operating environment, considers both the operating conditions under which the asset has to operate and the operator’s skills. Several studies have indicated that 40% or more of all failures are the result of operational errors or lack of understanding. Organizations need to ensure that operators are appropriately educated and trained in operating these assets without causing operational errors that lead to failures. In fact, operators should be the first line of defense both in monitoring the asset’s performance and any abnormal conditions and in initiating timely corrective actions.
The third factor is a maintenance plan that defines how the asset will be maintained. The objective of a good maintenance plan is to sustain asset reliability and to improve its availability. The plan should include the necessary maintenance and service-type actions needed to detect potential failures before they lead to unscheduled downtime.
Reasons for Not Implementing Best Practices
Over the years, the author has conducted many maintenance and reliability best practices workshops and has discussed failures of implementing best practices with hundreds of participants. These discussions concluded that the top 10 excuses or reasons for failure in implementing best practices are:
1. We thought we had a better way.
2. Our current process was working—why change?
3. We tried this before, and it didn’t work.
4. It was too hard.
5. We didn’t understand why it was necessary.
6. We didn’t trust our system vendor.
7. The vendor told us it was not necessary.
8. Our company (our process) is different (unique).
9. We could not afford it.
10. We did not have the time.
Examining these excuses, we can derive these four fundamental reasons not to implement best practices:
• Failure to understand the business operational risks
• Inability to correlate best practice cause and effect
• Fear of change
• Budget and schedule constraints
So what do best practices have to do with these principles of maintenance and reliability? Throughout the many years of the maintenance and reliability industry, good and bad practices have been identified. These practices, both the good and the bad, have been brought up in briefings at national and international conferences, discussed in person and over the airwaves, and written about in magazines, books, websites,and blogs. The best of these practices are now becoming more accepted and more widely published at the local, national, and international level,becoming the benchmarks that companies seek to achieve. Throughout this book, we will be discussing best practices related to maintenance,reliability, and asset management and how they can be implemented effectively to improve asset performance and reduce the overall cost of asset ownership.
Examples of Maintenanceand Reliability Benchmarks
What are the best practices in the maintenance and reliability field, and how can they be implemented to get better results? M&R best practicesare practices that have been demonstrated by organizations that are leaders in their industry. These companies are the quality producers with very competitive costs, usually the lowest in their industry. Figure 1.2 lists a few examples (by no means an exhaustive list) of maintenance and reliability best practice benchmarks along with their related typical world-class values. Benchmarks are discussed in more detail in Chapter 9.
The first value shown in Figure 1.2, maintenance cost as a percentage of replacement asset value (RAV), is a maintenance performance measure used extensively as a benchmark for evaluating best practices. We can immediately identify the cost differences between companies that are typical and companies that are world class or best in class. However, typical companies are likely to spend more to build up their maintenance and reliability program. Then, once they have achieved the desired level of reliability and availability, they should be able to reduce the maintenance cost by continuing to apply the best practices.
FIGURE 1.2 Comparing Best Practices Benchmark
We need to be very diligent in using these benchmarks for comparative purposes because definitions of these benchmarks can vary from one organization to another. It is significantly important to ensure that the terms used by the two organizations have the same meaning. The performance measures in Figure 1.2 have been included to demonstrate this.
Note: The Society for Maintenance & Reliability Professionals (SMRP) has done an excellent job defining and standardizing many of these benchmark metrics. The author has been involved with that effort for many years.
The details of a few maintenance and reliability best practice benchmarks along with their related typical world-class values as shown in Figure 1.2 are as follows:
1. Maintenance cost as a percentage of RAV. This measure is calculated as maintenance cost divided by the replacement asset value. In this benchmark, two factors must be defined in order to ensure a comparison is accurate:
a. Maintenance cost. This cost of maintenance for a plant or facility includes maintenance labor, maintenance materials,contractors used to perform maintenance work, capital maintenance, and the cost of all projects to replace worn-out assets.
b. RAV. The replacement asset value typically comes from engineering or the company’s insurance carrier and not from accounting. It is not the book value considered for accounting purposes. Instead, it is the current replacement cost of all assets for an industrial facility. This measure should include both the cost of removing old assets and the cost of installing new ones.
2. Maintenance material cost as a percentage of RAV. This benchmark is very similar to the previous measure. It is calculated simply as maintenance material cost divided by the replacement asset value. In most organizations, the material cost is easiest to obtain from the computerized maintenance management system (CMMS) or the organization’s financial system. To ensure a comparison is accurate, we must ensure that the maintenance cost includes all maintenance material purchased for all assets in a plant, including maintenance storeroom parts and material, parts and material used by contractors on maintenance, and capital maintenance work.
Caution: Organizations need to understand that neither maintenance cost nor maintenance material cost can be reduced in a sustainable manner without the application of best practices. Many organizations attempt to focus solely on maintenance cost reduction, but this approach is usually misdirected until they have reviewed and improved their processes and applied best practices.
3. Schedule compliance. This measure is the ratio of maintenance labor hours consumed for the jobs or tasks completed (which were on an approved schedule) divided by the total maintenance labor hours available during that period. Some organizations also track the number of jobs or tasks completed that were on an approved schedule versus the total jobs or tasks on a schedule.
Maintenance schedule. The maintenance schedule identifies jobs or tasks to be completed and approved in the previous week or at least 3 days in advance. It should cover 100% of maintenance labor.
For example, organization A is typical; its schedule compliance is 40%. Organization B has applied best practices and has a schedule compliance of 80%. This comparison indicates that organization B is actually getting twice as much scheduled work out of its maintenance staff as organization A. When schedule compliance is high, we usually find that organizations also have high uptime and asset utilization rates. There is a direct correlation between them.
4. Percentage of planned work. This measure calculates the percentage of maintenance work orders where all parts, material,specifications, procedures, tools, etc., have been defined prior to scheduling the work. This best practice is a key to the long-term success of any successful maintenance organization.
For example, a typical organization A has a percentage of planned work measured at 30%, whereas organization B has a percentage of planned work measured at 90%. This comparison indicates that organization B is proactively planning three times more work and will typically have high uptime and a high asset utilization rate. Organization B’s maintenance cost is also low because unplanned work costs more to execute.
5. Production/operations breakdowns losses. This number becomes small and insignificant as best practices are applied and become a normal way of life. One important issue that directly impacts this benchmark is that all personnel from executives to production operators must be responsible for the plant’s assets. The organization management must support the journey to excellence in implementing best practices. Operators must see assets as something they own. The only way this transformation can occur is through education and empowerment.
6. Parts stockout rate. This measure is based on the number of times a maintenance employee visits the storeroom to get the parts needed versus how often parts are supposed to be in the storeroom but are not available in stock.
In working with many organizations over the years, we’ve noted that benchmarking is not an easy process, particularly when there are no standard definitions of terms to benchmark. For example, RAV may not have the same meaning to organization A as it does to organization B. They may have different definitions. This problem has been a major challenge in M&R-related benchmarking initiatives. To support standardization of terms, the author has published an Uptime Elements:Dictionary for Reliability Leaders & Asset Managers.
When measuring performance against known benchmarks of best practices, we will find that all benchmarks are interconnected and interdependent. This is why an organization must have a clearly defined group of maintenance and reliability processes to implement best practices. Tailoring a best practice to your work environment is essential to a successful and effective implementation.
Thus far, we have discussed just a few examples of best practices and their benchmarks. Throughout this book, we will be discussing practices that may be standard, good, or best, depending upon where you stand in your journey for excellence in maintenance and reliability.
Basic Test on Maintenance and Reliability Knowledge
Many maintenance and reliability practitioners have not been successful in implementing best practices. It is usually because there is a lack of or limited understanding of the best practices or because management is not getting adequate support. Take the following test to assess your knowledge of M&R best practices. This test will help you understand where you stand in your reliability journey.
Once you complete the test, go to Appendix A and score yourself appropriately. Try not to guess when answering any of the questions. If you are uncertain, skip the question and review the text later; otherwise,your results may give you a false sense of how well you know “best practices” when it comes to maintenance and reliability.
1. Best practices are practices that are defined and applied by an organization to improve its operation. These practices may or may not be proven, but results are found to be acceptable.
a. True
b. False
2. Maintainability is measured by PM schedule compliance.
a. True
b. False
3. All maintenance personnel’s time should be covered by work orders.
a. True
b. False
4. Operations and maintenance must work as a team to achieve improved OEE.
a. True
b. False
5. A best practice is to have 90% or more of all maintenance work planned.
a. True
b. False
6. 100% of PM and PdM tasks should be developed using FMEA/RCM methodology, at least for critical assets.
a. True
b. False
7. Utilization of assets in a world-class facility should be above 85%.
a. True
b. False
8. 100% of maintenance personnel’s (craft/technician) time should be scheduled.
a. True
b. False
9. Time-based PMs should be about 30% of all PMs.
a. True
b. False
10. The 10% rule of PM should be applied on critical assets.
a. True
b. False
11. Most emergency work orders should be written by production/operations.
a. True
b. False
12. It is a common practice for operators to perform PMs.
a. True
b. False
13. The P-F interval can be applied to visual inspections.
a. True
b. False
14. Understanding of a P-F interval should help in optimizing PM frequency.
a. True
b. False
15. The best method of measuring the reliability of an asset is by counting downtime events.
a. True
b. False
16. The primary purpose of scheduling is to coordinate maintenance jobs for the greatest utilization of the maintenance resources.
a. True
b. False
17. What percentage of your assets should be ranked critical based on the risk to business?
a. Less than 30%
b. 30–50%
c. Over 50%
18. Vibration monitoring can detect uniform impeller wear.
a. True
b. False
19. Understanding the known and likely causes of failures can help design a maintenance strategy for an asset to prevent or predict failure.
a. True
b. False
20. Reliability can be improved easily after a maintenance plan has been put into operation.
a. True
b. False
21. What percentage of maintenance work should be proactive?
a. 100%
b. 85% or more
c. 50%
22. MTBF is measured by operating time divided by the number of failures of an asset.
a. True
b. False
23. Maintenance cost will decrease as reliability increases.
a. True
b. False
24. The “F” on the P-F interval indicates that equipment is still functioning.
a. True
b. False
25. A rule of thumb is that, on average, an experienced planner can plan work for how many craftspeople?
a. 10
b. 15
c. 20 or more
26. Which of the following is not a primary objective for implementing a planning process?
a. Reduce reactive work
b. Prevent delays during the maintenance process
c. Mesh the production schedule and the maintenance schedule
27. The best method of measuring the reliability of an asset is to know:
a. MTTR
b. MTBF
c. Both
28. With the exception of emergency work orders, planning and scheduling will benefit all maintenance work.
a. True
b. False
29. Leading KPIs predict results.
a. True
b. False
30. The sixth S in the 6S (also called 5S plus) process stands for safety.
a. True
b. False
31. RCM stands for:
a. Regimented centers of maintenance
b. Reliability-centered maintenance
c. Reliable centers of maintenance (uses best practices)
32. The objective of RCM is to preserve functions.
a. True
b. False
33. It does not cost anything to keep a part (material) in the storeroom after we bought and paid for it.
a. True
b. False
34. The inventory turnover ratio for an MRO store should be:
a. Less than 2
b. Between 4 and 6
c. Over 6
35. PM compliance is a lagging KPI.
a. True
b. False
36. Reliability is one key component of OEE.
a. True
b. False
37. Reliability and maintainability can only be designed in.
a. True
b. False
38. Creating a reliability culture from a reactive mode can be accomplished in a short period of time if enough resources are made available.
a. True
b. False
39. Karl Fischer’s coulometric titration method is an effective technique to determine the metallic content (in PPM) in an oil sample.
a. True
b. False
40. An IR thermography window is an effective method to satisfy NFPA 70E arc flash requirements.
a. True
b. False
41. FMEA is applicable only to assets currently in use.
a. True
b. False
42. RCM methodology can’t be used effectively on new systems being designed.
a. True
b. False
43. Properly training the M&R workforce can increase asset and plant (factory) availability.
a. True
b. False
44. TPM is a type of maintenance performed by the operators.
a. True
b. False
45. Lagging KPIs are the results of a process.
a. True
b. False
46. EOQ improves the inventory turn ratio.
a. True
b. False
47. New incoming oil from the supplier is always clean and ready to be used.
a. True
b. False
48. Which phase of the asset life cycle has the highest cost?
a. Design
b. Acquisition
c. O&M
49. Most of the maintenance costs become fixed:
a. After installation of the asset
b. During the operation phase
c. During the design phase
50. RCM provides the best results when used:
a. During operation (production)
b. During design/development
c. After an asset has failed or keeps failing
d. During build/fabrication
51. How soon we can restore an asset is measured by:
a. MTBF
b. MTTR
c. MTBMA
d. None of the above
52. Availability is a function of:
a. MTBF
b. MTTR
c. Uptime
d. Uptime and downtime
53. The failure rate of a component/asset can be calculated by knowing:
a. The number of failures
b. MTBF
c. MTTR
d. Uptime
54. The biggest benefit of a failure mode and effects analysis occurs during:
a. The operation phase
b. The maintenance phase
c. The design phase
d. None of the above
55. PM schedule compliance should be equal to or greater than 95%.
a. True
b. False
56. Maintainability is measured by:
a. The PM schedule compliance rate
b. The average time between maintenance actions
c. The percentage of time that equipment is working satisfactorily
d. The average time required to restore the equipment
57. Which process ensures that resources, material, and equipment are available before a job is performed?
a. Planning
b. Scheduling
c. Inventory
d. Workflow
58. Which analysis identifies a cost-effective approach to reduce maintenance and operational problems?
a. Weibull
b. FTA
c. Pareto
d. Bottleneck
59. When a task/job is completed, who should close out the work order in a CMMS system?
a. Person who did the work
b. Supervisor
c. Planner
d. Scheduler
60. The objective of an agreement between operations and maintenance is to:
a. Clarify who is responsible when a problem arises
b. Minimize confusion
c. Clarify roles and responsibilities
d. All of the above
61. Which work order characteristic (element) is most important?
a. Description of work completed
b. Cost of work
c. Asset ID
d. Cost/charge number
62. Which factor is most influential in developing the skills of the M&R team members?
a. Current maintenance repair skills
b. Current plant performance requirements
c. Future plant performance requirements
d. None of the above
63. The first stage of team development is known as:
a. Norming
b. Forming
c. Storming
d. Warming
64. Which maintenance strategy has a goal of zero defects, zero breakdowns, and an effective workplace design?
a. CM
b. TPM
c. RTF
d. CBM
65. A mission statement is a statement of an organization’s:
a. Structure
b. Roles and responsibilities
c. Purpose—what the organization wants to do
d. Net worth
66. In which phase of the asset’s life cycle is the highest cost incurred?
a. Design and procure
b. Build and install
c. Operate and maintain
d. Decommission and dispose
67. Optimizing inventory levels by ordering the right quantity at a specific time interval in order to minimize inventory cost, but still meet customer needs, is called:
a. Inventory cost analysis
b. Economy order quantity
c. Inventory turns analysis
d. Order cost analysis
68. Who is a stakeholder?
a. A person responsible for preparing the project budget
b. A person or organization that can affect, be affected by, or believe to be affected by a decision or activity
c. A person or organization that performs/supports change management to make a new improvement project succeed
d. A person or organization that is not involved in the project and whose interest will not be affected by the completion of the project
69. The last step in a basic communication model is to:
a. Decode
b. Encode
c. Provide feedback/response
d. Transmit a message
70. RPN (risk priority number) is the:
a. Sum of severity (S), occurrence (O), and detection (D)
b. Product of severity (S), occurrence (O), and detection (D)
c. Minimum value of severity (S), occurrence (O), and detection (D)
d. Maximum value of severity (S), occurrence (O), and detection (D)
71. What does a change agent do?
a. Supports change
b. Initiates change
c. Opposes change
d. Helps implement change
72. Which of the following is a reliability tactic?
a. Implementing a preventive maintenance program
b. Improving individual components to increase MTBF
c. Training technicians to improve repair time and reduce MTTR
d. Optimizing PM to reduce maintenance costs
73. TPM (total productive maintenance) has the potential of providing almost a seamless integration between:
a. Production and quality
b. Maintenance and quality
c. Production and maintenance
d. Production and engineering
74. The process that is intended to find potential failures and repair or replace bad components before they fail is known as:
a. Preventive maintenance
b. Failure-finding maintenance
c. Troubleshooting maintenance
d. Breakdown maintenance
75. A maintenance engineer has a list of pump failure modes and frequency of occurrence. Which of the following diagrams can help to prioritize maintenance tasks?
a. Ishikawa diagram
b. Bathtub curve
c. Pareto chart
d. Reliability growth diagram
76. A fault tree analysis (FTA) typically generates a
a. Set of statistical data
b. Report on the relative costs of design options
c. Diagram showing a hierarchy of failure causes
d. List for a specific plan of action
Please go to Appendix A to check the best answers to these questions. If your correct answers are:
• 68 or more: You have excellent M&R knowledge, but you should always continue to learn and enhance your knowledge.
• 45–67: You have a good M&R knowledge, but there is a potential for improvement.
• 44 or less: You have significant opportunities to improve.
A best practice is a technique or methodology that is found to be the most effective and has consistently shown to achieve superior results. When implemented appropriately, a best practice should improve performance and efficiency in a specific area. We need to understand that best practice is a relative term. A practice may be routine or standard to some, but to others it may be a best practice because their current practice or method is not effective in producing the desired results.
A best practice is often not what everyone else is doing, but is what is possible to achieve. It requires persuasive techniques that rely more on appeals than on force. A best practice usually requires a change in process; therefore, it needs to be accepted by all parties/stakeholders for successful implementation.
A best practice tends to spread throughout an industry after success has been demonstrated. However, demonstrated best practices can often be slow to implement, even within an organization. According to the American Productivity and Quality Center, the three main barriers to adoption of a best practice are a lack of:
1. Knowledge about current best practices
2. Motivation to make changes for their adoption
3. Knowledge and skills required to make changes
The workforce needs to have the knowledge of best practices in the area of maintenance and reliability in order to implement them effectively: A commitment to using the best practices in the M&R field and utilizing all the knowledge and technology at one’s disposal ensures success.
Remember that fundamental reasons not to implement best practices are:
• Failure to understand the business operational risks
• Inability to correlate best practice cause and effect
• Fear of change
• Budget and schedule constraints
Also, the performance of an asset is based on three factors:
1. Inherent reliability—how it was designed
2. Operating environment—how it will be operated
3. Maintenance plan—how it will be maintained
In later chapters, we will discuss all these factors in more detail so that we can achieve high asset performance throughout the asset life at minimum (optimum) cost.
Q1.1 Define a best practice. What are the barriers to implementing best practices?
Q1.2 What are key factors that impact the performance of plant machinery?
Q1.3 Why has reliability become a competitive advantage in today’s environment?
Q1.4 Identify five key performance measures in the area of maintenance and reliability. Elaborate on each element of these measures. What are typical “world-class benchmark numbers”for these performance measures?
Q1.5 Define what makes a benchmark “world class.” Discuss, using specific examples.
Q1.6 Define planned work and identify its benefits. What is a typical world-class benchmark number?
Q1.7 State and discuss four reasons that organizations fail to implement best practices.
References and Suggested Reading
Gulati, Ramesh, and Terrence O’Hanlon. 10 Rights of Asset Management. ReliabilityWeb.com, 2017. Gulati, Ramesh. Uptime Elements: Dictionary for Reliability Leaders &
Asset Managers. ReliabilityWeb.com, 2017. IW. Industry Week. Penton Media Publications, 2006–2008. Moore, Ron. Making Common Sense to Common Practice: Models for Operational Excellence. 5th ed.
SMRP and IMC (International Maintenance Conference). Annual Conference Proceedings, 2008–2019.
