The Short Version: RCM (reliability-centered maintenance) is a process for deciding how to manage the failures of an asset, so its output is a failure-management policy. FMEA (failure modes and effects analysis) is a process for identifying how an item or a process can fail and what happens when it does, so its output is a structured list of failure modes and their effects.
The two get treated as swappable, and they are not. One tells you the ways a thing breaks and what each break causes. The other uses that kind of information, along with other inputs, to decide how to manage those failures, including maintenance tasks or redesign. NASA describes rigorous RCM as based primarily on the FMEA. An FMEA can identify treatments, but that is not an RCM failure-management policy.
If you already know which one you need, the methods live in two separate guides: How to Perform RCM: Reliability-Centered Maintenance Methodology and How to Perform FMEA: Methodology and Worked Examples. This page is for the reader still deciding between them.
How We Evaluated
This guide is independent editorial analysis based on public catalogue entries and abstracts, plus NASA’s public RCM guide. The full texts of SAE JA1011 and the IEC standards are paywalled. Reliable does not sell reliability software, consulting, or certification and has no commercial interest in routing readers toward any particular method. Reliable does not accept payment for inclusion in this guide. Vendors may sponsor enhanced listings with additional detail, but editorial rankings are independent. Read our editorial policy. The facts below come from the SAE JA1011_202411 public catalogue, the IEC 60812:2018 public abstract, the IEC 60300-3-11:2009 public abstract, and NASA’s Reliability-Centered Maintenance Guide for Facilities and Collateral Equipment (September 2008).
What RCM Is
SAE JA1011, titled Evaluation Criteria for Reliability-Centered Maintenance (RCM) Processes, is the SAE standard that sets evaluation criteria for RCM processes. Its public catalogue entry describes it as a standard intended for use by any organization that has or makes use of physical assets or systems that it wishes to manage responsibly. The current version was published November 5, 2024, and the standard was first issued in August 1999. The full text is paywalled.
The IEC frames RCM as a means to an end. The public abstract for IEC 60300-3-11:2009 describes it as guidelines for the development of failure management policies for equipment and structures using RCM analysis techniques. It is an application guide, it applies to all industries, and it defines a revised RCM algorithm and approach. That phrase, failure management policies, is the useful part: RCM exists to produce a decision about how you will manage failures, not just a description of them.
NASA’s 2008 Reliability-Centered Maintenance Guide for Facilities and Collateral Equipment puts the same idea into four plain questions. What does the system or equipment do, and what are its functions? What functional failures are likely to occur? What are the likely consequences of those functional failures? And what can be done to reduce the probability of the failure, identify the onset of failure, or reduce the consequences of the failure? NASA presents these four questions, and they are NASA’s framing rather than the SAE JA1011 criteria. NASA states the goal as arriving at the most applicable, cost-effective maintenance technique through the identification of failure modes and their consequences. NASA traces the lineage to Nowlan and Heap’s 1978 Department of Defense report Reliability-Centered Maintenance (AD-A066579), which built an airline maintenance process around system functions, the consequence of failure, and failure modes.
The step-by-step method sits in the RCM how-to. What matters here is the shape: RCM ends in a failure-management policy, which can include maintenance tasks or redesign.
What FMEA Is
FMEA is a failure analysis method. The public abstract for IEC 60812:2018 explains how FMEA, including the FMECA variant, is planned, performed, documented, and maintained. Its stated purpose is to establish how items or processes might fail to perform their function so that any required treatments can be identified. It is a systematic method for identifying modes of failure together with their effects, both locally and globally. The analysis may include the causes of failure, and the failure modes can be prioritized to support decisions about treatment.
FMEA and FMECA are close relatives. Per the same abstract, the analysis is called FMECA when the criticality ranking involves at least the severity of consequences, and often other measures of importance as well. The standard applies broadly: hardware, software, processes including human action, and the interfaces between them. It is a generic standard and offers no specific safety-application guidance. The third edition was published August 10, 2018, and the public abstract notes that this edition introduced alternative RPN calculations and a criticality-matrix method. The full text is paywalled.
NASA describes FMEA in the same functional terms in section 4.2 of its 2008 guide. FMEA is applied to each system, subsystem, and component inside the analysis boundary. It addresses each system function, all possible failures, and the dominant failure modes of each failure, then examines the consequences of those failures on the mission or operation, on the system, and on the machine itself. The worked method, including how to build the tables, lives in the FMEA how-to. The shape to hold onto: FMEA identifies failure modes and effects, and those modes can be prioritized to support treatment decisions. That is not the same as an RCM failure-management policy.
Where They Overlap
The clean line between the two blurs in practice, and NASA’s guide is candid about why. It notes that the role of RCM has expanded past the development of maintenance tasks based on FMEA. In other words, FMEA was historically the engine inside RCM, and RCM grew to include more than that engine. NASA also describes a spectrum of RCM strategies that vary from run-to-failure at one end to a streamlined FMEA combined with predictive testing and inspection at the other. RCM, as NASA integrates it, ties together preventive maintenance, predictive testing and inspection, reactive repair, and proactive maintenance.
The connection runs deepest in rigorous RCM. NASA states that rigorous RCM is based primarily on the FMEA, while intuitive or streamlined RCM applies the same principles but does not analyze every failure mode. So when someone says they “did an FMEA as part of RCM,” they are describing NASA’s rigorous RCM path, where the FMEA supplies the failure modes and the RCM logic decides what to do about each one.
One nuance carries across both methods and is worth stating plainly: the same failure mode can have different consequences depending on how the asset is used. NASA gives the ball-bearing example, where an identical bearing failure means one thing in one application and something else in another. Note that stitching SAE, IEC, and NASA into a single tidy definition is editorial synthesis on our part. The source documents were written by different bodies for different purposes, and they do not all use identical language.
RCM and FMEA Side by Side
| Method | Purpose | Typical output | Public source | When it fits | What it does not do |
|---|---|---|---|---|---|
| FMEA | Establish how items or processes might fail so required treatments can be identified | A structured list of failure modes and their effects, which can be prioritized | IEC 60812:2018; NASA 2008 section 4.2 | You need to identify how something fails | Write an RCM failure-management policy on its own |
| RCM | Develop a failure management policy for the asset | A failure-management policy that can include maintenance tasks or redesign | SAE JA1011_202411; IEC 60300-3-11:2009; NASA 2008 | You need to decide how to manage failures | Replace the failure analysis; rigorous RCM is based primarily on the FMEA |
When Each Fits a Plant
Reach for FMEA when the job in front of you is identifying how items or processes fail. That is exactly what IEC 60812 describes: a systematic way to surface failure modes and their effects so that treatments can be identified. Failure modes can be prioritized to support those treatment decisions. If your team needs to understand a new design, a modified line, or a troublesome asset, FMEA is the method that produces that list.
Reach for RCM when the job is a failure-management policy. IEC 60300-3-11 frames RCM around developing those policies. NASA frames rigorous RCM as producing appropriate maintenance tasks or redesign requirements. Deciding what to do about a failure is not the dividing line. IEC 60812 already lets FMEA identify treatments. You are in RCM territory when you are writing an RCM failure-management policy from that analysis.
You want both when you are running NASA-style rigorous RCM. NASA describes that path as based primarily on the FMEA. In that pattern the FMEA is not a competing choice. It supplies the failure modes the RCM logic then works through.
When Each Does Not Fit
FMEA alone does not write an RCM failure-management policy. IEC 60812 says FMEA identifies treatments and can support treatment decisions. It does not develop the failure management policy the way IEC 60300-3-11 describes RCM doing. A plant that finishes a thorough FMEA has a structured failure list, and it may name treatments. That is still not RCM.
RCM is the wrong label for a standalone design or process FMEA that never becomes a failure-management policy. If nobody is going to use the analysis to choose a failure-management policy, calling it RCM overstates what happened. It is an FMEA, and naming it accurately keeps your documentation honest for the next person who reads it.
A Worked Plant Example
The following is an illustrative example, not a real plant. Picture two teams at a fictional facility, Cedar Line Foods, both looking at the same asset: a boiler feedwater pump.
Team A runs an FMEA on the pump. They work through the pump’s functions, the ways it can fail to perform each function, the dominant failure modes behind each failure, and the effects locally and downstream. They come out with a list: seal failure, bearing wear, impeller erosion, and so on, each with its effect. That list is genuinely useful. It tells them where the pain concentrates. IEC 60812 says they can also identify treatments and prioritize modes. That still is not an RCM failure-management policy.
Team B takes that same failure-mode list and keeps going. Using the RCM logic, they ask what can be done about each mode: which failures justify a scheduled task, which are better caught by predictive testing and inspection, which are candidates for run-to-failure, and which point to a design or proactive change. They finish with a failure-management policy for the pump, including maintenance tasks or redesign.
Same pump, same starting analysis, two different stopping points. Team A produced an FMEA. Team B used that FMEA inside an RCM decision. Neither team “won,” and neither result is a purchase decision. They answer different questions, and a plant may need one, the other, or both depending on what it is trying to settle.
Honest Limitations
The full texts of SAE JA1011 and the IEC standards are paywalled. Everything attributed to them here comes from their public catalogue entries and abstracts, which describe scope and purpose but do not reproduce the standards’ internal criteria or procedures. If you need the SAE JA1011 evaluation criteria themselves, you will need the purchased standard.
The NASA guide we lean on most is a facilities and collateral equipment guide from September 2008. It is a public, detailed, and useful document, but it was written for NASA’s facilities context, and its four questions are NASA’s own framing rather than the SAE JA1011 criteria. Do not treat the two as identical.
FMEA and FMECA are not the same word for the same thing; FMECA adds criticality ranking. And we have deliberately avoided quoting industry averages or benchmark percentages here. NASA’s 2008 guide includes claimed maintenance-budget savings, ROI figures, and failure-pattern percentages; those were excluded because they are historical and context-specific.
Frequently Asked Questions
What is the difference between RCM and FMEA?
FMEA is a method for identifying how an item or process can fail and what the effects of those failures are, producing a structured list of failure modes. Those modes can be prioritized to support treatment decisions. RCM is a broader process for deciding how to manage those failures, producing a failure-management policy that can include maintenance tasks or redesign. FMEA analyzes failures. RCM uses that kind of analysis, among other inputs, to choose what to do about them.
Is FMEA part of RCM?
Often, yes. NASA describes rigorous RCM as based primarily on the FMEA, meaning the FMEA supplies the failure modes that the RCM logic then works through to decide on maintenance. Streamlined or intuitive RCM uses the same principles but does not analyze every failure mode, so it may not run a full FMEA.
Can I do FMEA without RCM?
Yes. FMEA is a standalone method under IEC 60812:2018 to identify failure modes for a design, a process, or an asset. It can identify treatments and can prioritize modes. That is not the same as an RCM failure-management policy.
Which one produces a failure-management policy?
RCM. IEC 60300-3-11 frames RCM around developing failure management policies, and NASA frames rigorous RCM as determining appropriate maintenance tasks or possible redesign requirements. FMEA identifies failures and can support decisions about treatment, but it does not by itself write that RCM policy.
What standards cover RCM and FMEA?
RCM is addressed by SAE JA1011, which sets evaluation criteria for RCM processes, and by IEC 60300-3-11, an application guide for developing failure management policies using RCM techniques. FMEA is addressed by IEC 60812:2018, which covers how FMEA and the FMECA variant are planned, performed, documented, and maintained. NASA’s 2008 facilities guide discusses both together.
Do I need both RCM and FMEA?
It depends on the question you are trying to answer. If you only need to understand how something fails, an FMEA may be enough. If you want an RCM failure-management policy of the kind IEC 60300-3-11 describes, that is RCM’s job. IEC 60812 already lets FMEA identify treatments, so deciding what to do is not exclusive to RCM. NASA describes rigorous RCM as based primarily on the FMEA.
Related Guides
- How to Perform RCM: Reliability-Centered Maintenance Methodology
- How to Perform FMEA: Methodology and Worked Examples
- How to Calculate Asset Criticality
- How to Start a PdM Program
- How to Calculate MTBF and MTTR
Sources
- SAE International – Evaluation Criteria for Reliability-Centered Maintenance (RCM) Processes (JA1011_202411 public catalogue)
- IEC – IEC 60812:2018 Failure modes and effects analysis (FMEA and FMECA) (public abstract)
- NASA – Reliability-Centered Maintenance Guide for Facilities and Collateral Equipment (September 2008)
