C-DRONE GUIDE · 22 JULY 2026
Drone-based gas and methane leak detection (LDAR): method, ICPE regulations and price
A refinery that must comply with the new LDAR obligations before the end of 2026, a Seveso site operator looking to cut fugitive methane emissions, or a gas storage manager after a faster method than a manual round with a handheld infrared camera: in all three cases, a drone fitted with an optical gas imaging (OGI) camera or an onboard laser sensor changes the equation. It flies over hard-to-reach areas in minutes — the roofs of storage tanks, elevated pipe racks, flare stacks — where a ground inspection means long, instrumented walks past every single component. Here is how this technology detects and quantifies a gas leak, the regulatory framework it falls under in France, and what it costs in 2026.
Published on 22 July 2026, reviewed on 7 August 2026 — regulations in force as of August 2026.
Why leak detection is becoming a regulatory obligation
A ministerial decree of 4 November 2024, published in the Official Journal on 19 November 2024, transposes into French law the European conclusions on best available techniques (BAT) and makes obligations to reduce and monitor diffuse volatile organic compound (VOC) emissions applicable — without waiting for each site's operating permit to be revised — to the regulated industrial sites concerned (ICPE): refineries, petrochemical plants, gas storage facilities, treatment platforms. Every operator had to file a review report before the end of 2023, comparing its existing equipment against BAT, with effective compliance expected by the end of 2026.
In practice, these obligations translate into an LDAR (Leak Detection And Repair) programme: an inventory of equipment that are sources of fugitive emissions (valves, flanges, drains, pump seals), a leak threshold above which a repair is triggered, periodic measurement campaigns and documented follow-up of repairs carried out. At EU level, Regulation (EU) 2024/1787 on methane emissions in the energy sector, in force since 4 August 2024, specifically requires oil and gas operators to run Type 1 LDAR campaigns (detecting large, so-called "super-emitter" leaks above 7,000 ppm) and Type 2 campaigns (smaller leaks, from 500 ppm), on a phased implementation timeline running until 2030.
How a drone detects and quantifies a gas leak
Two families of sensors equip leak-detection drones. The optical gas imaging (OGI) camera is a specialised infrared camera tuned to the absorption wavelengths of methane and many VOCs: the gas appears as a visible plume on screen, making it possible to pinpoint it precisely on a piece of equipment even where it is invisible to the naked eye. The laser sensor (TDLAS, tunable diode laser absorption spectroscopy) instead measures a concentration integrated along the path of the beam reflected off the ground — expressed in ppm·m — and, combined with mass-balance algorithms, can estimate a leak rate in kilograms per hour rather than a simple yes/no detection.
A review published in the journal Drones by Hollenbeck, Zulevic and Chen (2021) surveys methods for detecting and quantifying methane emissions with small unmanned aircraft systems, comparing optical imaging and onboard laser sensors (see the study on Google Scholar). A more recent study by Tassielli, Cananà and Spalatro (2024) in the journal Sustainability tested a drone-mounted TDLAS system under controlled methane release trials, to identify the variables that disturb the background-noise measurement — wind speed, distance to source, flight height — ahead of deployment on storage facilities or landfills (see the study on Google Scholar). Both publications agree on one point: drone reliability depends heavily on flight conditions, which calls for a rigorous mission protocol rather than a simple flyover.
The regulatory framework for flying over a regulated industrial site
A leak-detection mission flies over equipment at low altitude and within the remote pilot's direct line of sight: it most often falls under the open category, sub-category A2, whenever personnel work near the equipment being surveyed. A wider perimeter requiring a beyond-visual-line-of-sight (BVLOS) flight to cover an entire platform shifts into the specific category, under the same STS-01/STS-02 standard scenarios used for site surveillance — see our guide to industrial site surveillance by autonomous drone.
The main difficulty does not come from the airspace but from site access: a Seveso site or an ICPE subject to authorisation applies its own safety rules, independent of any aviation rule — remote pilot clearance, a prevention plan, and above all the management of ATEX zones (potentially explosive atmospheres), where any uncertified equipment, drones included, may be banned in the immediate vicinity of a leak source. Our guide to industrial chimney and silo inspection by drone covers these confined-space ATEX constraints in detail. As with any professional mission, the operator must be registered on AlphaTango, regulated zones must be checked on the Géoportail map, and professional third-party liability insurance covers the flight itself — separate from the site access authorisation issued by the site operator.
What the drone changes compared with a manual OGI round
The reference method for an LDAR programme remains the handheld OGI camera: a trained operator walks the site component by component, pointing the camera at every listed valve, flange or drain. On a large platform, this exhaustive round takes several days and leaves little time for the hardest-to-reach areas — the roof of a storage tank, an elevated pipe rack, the top of a flare stack — which the operator can only inspect using rope access or an aerial platform.
The drone does not replace this component-by-component round, but it speeds up the screening phase: a first wide flyover of the area quickly locates visible OGI plumes or abnormal laser concentrations, so the detailed manual inspection can then focus on the spots flagged as suspect. On elevated areas normally out of reach without heavy access equipment, it instead allows direct detection without waiting to mobilise an aerial platform or a rope-access team. This complementarity matches the spirit of the EU text itself: Regulation (EU) 2024/1787 explicitly cites drone-mounted sensors as one of the mobile monitoring solutions able to cover a large area quickly and accurately.
The price of a drone leak-detection mission in 2026
The price mainly depends on the number of components to cover, the size of the site and the type of sensor used (qualitative OGI or quantitative laser). Orders of magnitude observed in France in 2026:
| Service | Observed price (excl. VAT) |
|---|---|
| OGI screening flyover, small site (a few dozen components) | €800 to €1,500 |
| Drone LDAR campaign, medium industrial site (one day) | €2,000 to €4,500 |
| Laser (TDLAS) quantification with flow-rate estimate | +30 to 50% over an OGI-only screening |
| Multi-year campaign with LDAR compliance report | quoted individually, depending on frequency and number of sites |
This price should be weighed against a full manual OGI round, which takes longer on a large site but remains necessary at component level: the drone is generally not billed as a replacement for that round, but as a complement, to speed up screening over large or hard-to-reach areas and document a baseline before intervention. Many operators fold this service into their annual ICPE compliance audit rather than commissioning it as a standalone mission.
Frequently asked questions about drone gas leak detection
Does the drone replace the handheld OGI camera? No: it speeds up screening over a large or elevated area, but the detailed component-by-component inspection required by an LDAR programme is still carried out on the ground or via close access.
Can a drone fly in an ATEX zone? It depends on the zone's classification and the equipment's certification: some ATEX zones close to an active leak source remain off-limits to any uncertified equipment, drones included — the call is made by the site operator, together with its safety officer.
Is drone detection enough on its own to prove LDAR compliance? It forms one part of the compliance file, but an LDAR programme also requires an exhaustive inventory of components, a defined leak threshold and documented follow-up of repairs — the drone speeds up data collection, it does not stand in for the programme on its own.
What is the difference between VOCs and methane in this context? The VOC obligations cover a broader set of volatile organic compounds under French ICPE regulations, while Regulation (EU) 2024/1787 specifically targets methane for energy-sector operators; the two frameworks overlap heavily on the same equipment and the same detection methods.