Most lightning risk assessments begin with a boundary: this building, this substation, this plant. The site has a fence, and the risk is understood to live inside it. That framing works well when the asset is a single structure. It breaks down completely for the operators whose asset is not a place but a line drawn across a landscape.
Pipelines, transmission and distribution networks, rail corridors, and remote telemetry systems share a defining feature: the asset is distributed across tens or hundreds of kilometres, and the exposure travels with it. There is no single site to protect. There are many small, scattered, and frequently unmanned points, and every one of them is a place where lightning can enter the system.
The single-site assumption breaks
When protection is scoped around one structure, you can concentrate attention, inspection, and investment in one place. A distributed network denies you that convenience. A cathodic protection rectifier, a valve actuator station, a sectionalising switch, a telemetry outstation: each is a node with its own exposure, its own earthing, and its own consequences if a strike gets in. The network is only as resilient as its weakest node, and the weakest node is usually the one furthest from anyone's routine attention.
Worse, the connections between nodes become part of the problem. Long conductive runs, whether pipe, rail, cable, or the earth itself, couple the nodes together. A strike at one point can drive current and elevated potential along the route to equipment far away, so a node can be damaged by an event that never came near it. Distance does not isolate; in these systems it often connects.
Each node deserves its own risk picture
The standard already anticipates this. IEC 62305-2 assesses lightning risk structure by structure, on the basis of each one's exposure, construction, contents, and consequences of failure. Applied to a distributed network, that means a remote instrument hut on an exposed ridge and a control building in a sheltered valley are simply not the same risk, and should not receive the same protection by default.
The unmanned-site problem
Distributed assets carry a second difficulty that fixed sites largely escape: most nodes are visited rarely, if at all. A degraded earth connection or a spent surge protection device at a staffed facility tends to be noticed. The same fault at a remote outstation can persist unseen for years, until a strike finds it and the first anyone hears of it is a lost signal or a damaged asset.
This is what makes condition, and not just design, the central question for distributed networks. A protection scheme that was sound when commissioned is worth little if a fraction of its nodes have quietly failed and nobody has been past to measure them. Coverage and verification matter as much as the original engineering.
Protecting the network, not just the nodes
The practical answer is to treat the network as a portfolio of risks to be ranked and managed, rather than a single object to be certified. That means identifying which nodes carry the greatest exposure and the heaviest consequences, protecting those to the standard they warrant, and putting the whole population on a verification cycle so that degradation at any node is caught by measurement rather than by outage.
Our risk assessment work is built to handle this node-by-node, using the IEC 62305-2 framework to distinguish the exposed and critical points from the routine ones, so protection effort follows the risk. For assets spread across a landscape, that discrimination is the difference between a protection budget that is spent where it counts and one that is spread too thin to matter anywhere.
Do you know which of your nodes is the weakest?
Across a distributed network, the vulnerable node is rarely the obvious one. We can map lightning risk across your assets and rank where protection is actually needed.
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