C-DRONE GUIDE · 31 JULY 2026
Hydrocarbon storage-tank drone inspection: shell, roof, corrosion, ATEX, price
Large tanks storing hydrocarbons, chemicals or industrial water are among a site's most closely watched structures: their failure has major environmental and safety consequences. External inspection — shell, roof, coating, nozzles, weld seams — usually demands scaffolding, a man-lift or rope-access technicians, in an explosive atmosphere and under strict work permits. The drone documents much of this visual inspection from outside, with no contact surface and no ignition source near the wall, and without taking the tank out of service. It replaces neither the statutory inspection plan nor thickness measurements: it becomes their fast, safe visual layer. Here is what it inspects, its ATEX framework, and prices observed in 2026.
Published on 31 July 2026, reviewed on 12 August 2026 — regulations in force as of August 2026.
What the drone records on a tank
Seen up close and over its full height, a tank reveals: external corrosion of the shell and roof, blistering and flaking of the coating, rust runs at weld seams, condition of nozzles, ladders, handrails and crowns, deformations, and on floating roofs the visible state of the perimeter rim seals. A thermal flight sometimes complements the visible one to show the fill level or surface anomalies.
The effectiveness of this approach is established. A study by Ali and co-authors published in 2023 in Drones describes a UAV system that images the exterior surface of oil tanks and automatically detects defects, notably rust, positioning the drone as an alternative to human climbing and robots (see the study on Google Scholar). That is exactly the service: exhaustive visual coverage of the envelope, obtained without scaffolding.
Flying in ATEX zones and on Seveso sites
A hydrocarbon depot is an explosive-atmosphere (ATEX) environment, often Seveso-classified: the flight is prepared with the HSE department and the operator. Key points: define safety distances to vents and classified zones, comply with the work-permit regime, choose a compatible slot and configuration (the drone is an electric aircraft; it operates at a safe distance from vapour-emission sources, never in contact with or above a venting outlet). The surrounding airspace is checked on Géoportail, as these sites are sometimes near aerodromes or in regulated zones.
This rigorous preparation is the counterpart of a major safety gain: no technician exposed at height in contact with a tank, no scaffolding to erect in a classified zone. The drone here joins the logic of our confined-space inspection and transport pipeline monitoring guides for industrial-risk sites.
A link in the inspection plan, not a substitute
A regulated tank falls under an inspection plan combining visual examinations, ultrasonic thickness measurements, floor and shell checks, often with periodic openings. The drone provides the exhaustive external visual examination; it does not measure a plate's residual thickness and does not inspect the inside of an in-service tank. A review by Stoicescu, Ripeanu, Tănase and Toader published in 2025 in Materials situates the drone precisely among tank condition-assessment methods — high-resolution imaging combined with thickness measurements — and highlights the cost, scheduling and safety gains over scaffolding (see the study on Google Scholar).
Good practice makes the drone the targeted trigger of heavy checks: it spots the corrosion or degraded-coating zone, the expert then decides where to run thickness measurements and deeper investigations. You inspect more often, target better and take out of service only what must be.
Prices observed in 2026
Ranges observed in 2026 (excl. VAT):
- External visual inspection of one tank (shell + roof, geolocated photo report): €600 to €1,300.
- Bank of several tanks on one depot (campaign coordinated with HSE): €1,300 to €3,500.
- Thermography / 3D survey option (corrosion monitoring, structure model): €500 to €2,000.
- Periodic inspection programme (regular passes, visit-to-visit comparison): quoted.
The flight is scheduled for a slot and configuration validated by the operator in the ATEX zone. Request a quote stating the type and number of tanks, the stored product, the site classification and the goal (visual check, corrosion monitoring, shutdown preparation).