Running a leak detection and repair (LDAR) programme
Leak detection and repair (LDAR) is a recurring programme to find and fix fugitive emissions of process gas and vapour from valves, flanges, pumps and connectors. It uses gas-imaging cameras or sniffing instruments to locate leaks, tags them, drives prioritised repairs and re-monitors — protecting safety, the environment and product yield.
What it is
Fugitive emissions are the small, continuous leaks from the thousands of sealed joints in a process plant — each individually minor, collectively significant. An LDAR programme inventories the leak-prone components, monitors them on a schedule with optical gas imaging or portable analysers, classifies findings against a leak threshold, and feeds repairs into maintenance, then verifies them on re-survey.
Why it is done
Fugitive emissions waste valuable product, create fire, explosion and health hazards, and increasingly fall under emissions regulation. Because the leaks are invisible and silent, they persist indefinitely unless deliberately hunted. A systematic programme catches them early, prioritises the worst emitters, and demonstrably reduces both loss and risk in a way that ad-hoc inspection cannot.
How it is done
Leak-prone components are inventoried and tagged, and a monitoring method chosen — optical gas imaging for fast wide-area scanning, instrument sniffing for quantified concentrations. Components are surveyed on a defined cycle, leaks above the action threshold are logged and ranked, and prioritised repairs are scheduled. Repairs are confirmed effective by re-monitoring, and persistent leakers may be redesigned to lower-emission seals.
- Inventory components
- Choose detection method
- Survey on cycle
- Classify against threshold
- Prioritised repair
- Re-monitor & confirm
What to watch for
A monitoring-only programme that never closes repairs simply documents emissions without reducing them. Setting the action threshold by convenience rather than risk, and ignoring difficult-to-reach components, both leave the largest emitters in place.
Related practices
Transitioning to condition-based maintenance
Rolling out reliability-centred maintenance
Running an asset criticality ranking exercise
Related topics
Thermography (Infrared Inspection) · Root Cause Analysis (RCA) · Carbon Footprint
Common in: Chemicals · Power Generation · Pharmaceuticals · Paper & Packaging