Root Cause Analysis, V1
A structured root cause analysis framework to guide teams through the systematic investigation of failures, incidents, or process deviations, ensuring all contributing factors are identified, corrective actions are established, and findings are documented to prevent recurrence and drive ongoing operational improvement.
Foothills RNG Facility
02/26/2026
Root Cause Analysis, V1
The purpose of Root Cause Analysis (RCA) for a major equipment failure is to identify the fundamental cause of the problem—not just the immediate symptoms—so that effective corrective actions can be implemented to prevent recurrence. It helps improve equipment reliability, reduce downtime and repair costs, enhance safety, and strengthen maintenance and operational practices.
Event Initiation
What triggers the need for a RCA?
Event Initiation
if the answer is "allOf [Unplanned Shutdown over 3hrs,Membrane performance Degradation over 25%,Compressor trip recurring 2+ times in 1 day,Catastrophic failure of equipment ,Production loss over 300 Dt,Any reactive event over 8 man hours]"
Event type
Immediate Action
Stabilize situation and perform LOTO, ECP
Define the problem
Fact based problem statement
Asset
System Type
Date/Time of failure
Exact failure mode
Trip/Alarm name
Impact (Lost DT, hrs of downtime, $ for repairs, Lost hrs of availability of equipment, Internal man hours for repair)
Data Collection
Any data collection point that touches the equipment that failed
Trend at least 12hrs before event and upload
Example: Inlet pressure/ temp Outlet pressure/ temp Differential pressures Gas composition Flow rates
Add or drag pictures
Equipment Health Data Trend
Example: Motor Amps VFD faults Oil Pressure Vibration readings Oil Analysis Cycle hours Pressure ratios Equipment hours
Add or drag pictures
Maintenance History
Date of Last PM
Description of last PM performed
Most recent repairs
Quick description, then please add WO #
List all Bypasses/adjustments in place
List all Temporary repairs in most recent operation
Process factors
Causal Analysis
Structured off the DOE method
Event timeline
What happened in chronological order?
5 Why, ASQ discipline
Why 1
Why 1 Support/Answer
Why 2
Why 2 Support/Answer
Why 3
Why 3 Support/Answer
Why 4
Why 4 Support/Answer
Why 5
Why 5 Support/Answer
Root Cause Classification
Root Cause Category
if the answer is "oneOf [Other]"
What?
if the answer is "allOf [Design Limitation,Maintenance program gap,PM missed/postponed,Procedure deficiency,Training gap,System management weakness]"
Why? And what should have been done?
if the answer is "allOf [Instrumentation failure,Alarm/Control tuning issue,Equipment worn out,Component catastrophic failure,Enviromental,Feed Gas Variation]"
Why? Back up, and look at the whole picture
Corrective Actions
Immediate Fix
Recurrence Prevention, procedural
Changed PM schedule, changed tuning, modified PM procedure Please add: Owner Due date Verfication
System Improvement, Hardware
Added Sensors, upgraded parts, more/less something
Effectiveness Review
Has the failure reoccurred?
if the answer is "oneOf [YES]"
if the answer is "oneOf [NO]"
Has it been at least 30 days?
if the answer is "oneOf [No]"
if the answer is "oneOf [Yes]"
Learning
Review RCA with others
Source: Foothills RNG Facility (Community Member)