Shell deformations, progressive ovalization, and bottom settlement: the geometric alterations of atmospheric storage tanks can compromise the structural integrity of the installation and lead to operating conditions that do not comply with safety standards. The inspections required by API 650 and API 653 demand measurement methodologies capable of detecting even millimetric deviations on large structures and of accurately documenting the actual geometric condition of the tank compared to the original design specifications. To meet this need, Italsabi has integrated 3D laser‑scanner surveying into its non‑destructive testing services: a next‑generation technology that ensures high‑precision geometric acquisition with reduced execution times. 3D Laser Scanner Technology 3D laser‑scanner surveying is based on the digital acquisition of the tank’s three‑dimensional geometry through the generation of point clouds. A laser beam scans the surface of the vessel, capturing millions of spatial coordinates in just a few minutes and producing an accurate, high‑resolution reconstruction of the actual structure. The ZF 5024 ADVANCED system used by our specialists offers: A range of up to 150 meters, allowing effective operation even on large‑scale tanks; Four resolution levels and two quality modes to adapt the measurement to the specific inspection requirements; Metric readings completed in just 52 seconds, ensuring rapid execution without compromising data accuracy. The processing workflow converts the acquired data into a three‑dimensional digital model using dedicated software. The resulting information is then analyzed to compare real measurements with design specifications and regulatory tolerances, enabling the identification of deviations, deformations, or geometric anomalies. An archive of surveys makes it possible to monitor the progression of deformations over time and plan maintenance interventions more effectively. Additionally, the generated point clouds can be reused later to verify measurements and distances not initially included in the scope of the inspection—such as the size of a roof truss, the length of a nozzle, and more. Compliance with API 650 and API 653 Standards API (American Petroleum Institute) standards define the reference framework for the design, construction, and inspection of atmospheric storage tanks used in the petroleum, chemical, and process industries. API 650 specifies the requirements for the construction of welded steel tanks for liquid storage. API 653 regulates the inspection, repair, alteration, and reconstruction of existing tanks. 3D laser‑scanner surveying enables precise verification of the geometric parameters required by these standards. Full acquisition of the base‑ring geometry allows for a planimetric and altimetric assessment of the annular region of the tank, which is essential for evaluating support uniformity and identifying differential settlement. Verticality checks of the shell—measuring deviations both at the top and along each course—allow detection of deformations caused by mechanical forces, thermal effects, or ground movement. Ovalization analysis verifies distortion of the tank’s circular profile, which may result from internal overpressure, construction defects, or uneven soil settlement and can compromise overall structural equilibrium. These inspections are complemented by assessment of bottom deformations, which may indicate localized settlement, advanced corrosion, or foundation issues. Certified Inspection Reports At the end of each inspection, a certified technical report is issued, documenting all measurements performed, comparing the recorded values with the allowable tolerances defined by API standards, and providing technical conclusions regarding the tank’s compliance status. This document is essential for the facility’s technical records and for planning maintenance activities. It is important to note that performing the survey requires specific operational conditions. The duration of the work depends on clearing the inspection area of scaffolding, platforms, or ongoing operations. For insulated tanks, measurements must be taken from inside the vessel, following confined‑space safety procedures and ensuring full protection for personnel. Applications of 3D Surveying 3D laser‑scanner surveying is applicable throughout the entire lifecycle of atmospheric tanks. API 653 requires periodic compliance inspections to verify that the vessel maintains structural integrity over time; 3D surveying provides the technical documentation needed to demonstrate compliance. After construction or major repair work, the surveys verify that final dimensions match project specifications. Tanks subjected to demanding operating conditions require regular monitoring. By comparing multiple three‑dimensional configurations, operators can track progressive deformations and assess long‑term geometric evolution. This service integrates effectively with other non‑destructive testing solutions offered by Italsabi, such as Floormap inspection of the tank bottom using Magnetic Flux Leakage (MFL) technology. Italsabi’s Excellence in Geometric Surveying We conduct 3D laser‑scanner surveys throughout the national territory, ensuring a fully integrated approach—from on‑site data acquisition to digital processing and final technical reporting. When original technical drawings or design specifications are unavailable, Italsabi provides specialized support through its certified engineers. This enables us to produce complete technical evaluations of tank compliance even in the absence of full documentation, assessing the structure in accordance with applicable laws and industry best practices. 3D laser‑scanner surveying is an advanced tool for managing atmospheric storage tanks, offering precise and rapid measurements along with accurate compliance verification according to API 650 and API 653 standards. Digital geometry acquisition provides objective data for evaluating structural condition and planning targeted maintenance interventions, enabling a predictive approach that optimizes costs and prevents safety‑related issues.