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Point of strike Example Type of damage Type of loss

D1 L1, L4 b
Structure D2 L1, L2, L3, L4
S1
a
D3 L1 , L2, L4

Near structure D3 L1 , L2, L4
a
S2

D1 L1, L4 b
Incoming line
S3 D2 L1, L2, L3, L4
a
D3 L1 , L2, L4

Near incoming line D3 L1 , L2, L4
a
S4

a For hospitals and other structures where failures of internal systems immediately endangers human life and structures with a risk of
explosion.
b For agricultural properties (loss of animals)
Table 3.2.1.1 Sources of damage, types of damage and types of loss depending on the point of strike

These types of loss can arise as a result of different types where
of damage. The types of damage thus literally represent the N x is the number of dangerous events, i.e. the frequency
“cause” in a causal relationship, the type of loss the “effect” of lightning strikes causing damage in the area un-
(Table 3.2.1.1). The possible types of damage for one type of der consideration (How many dangerous events occur
loss can be manifold. It is therefore necessary to first define the each year?);
relevant types of loss for a structure before defining the types
of damage to be determined. P x is the probability of damage (What is the probability
that a dangerous event causes certain damage?);
L x is the loss factor, i.e. the quantitative evaluation of
3.2.2 Fundamentals of risk analysis damage (What are the effects, amount of loss, extent
According to IEC 62305-2 (EN 62305-2), the risk R that light- and consequences of a certain damage?).
ning damage occurs is the sum of all risk components R x rel- Therefore, the function of a risk analysis is to determine the
evant to the particular type of loss. The individual risk compo- three parameters N x , P x and L x for all relevant risk components
nents R x are derived from the following equation: R x . A comparison of the risk R with a tolerable risk R T provides
information on the requirements for and dimensioning of light-
R = N P L
x x x x ning protection measures.

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