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r L c c s is the value of the internal systems in the zone includ-
L = L = t T a ing their activities;
A U c
t c t is the total value of the structure (sum of all zones
r r L (c +c +c +c ) for animals, buildings, contents and internal systems
L = L = p f F a b c s including their activities).
B V c
t IEC 62305-2 (EN 62305-2) specifies typical mean values for L T ,
L c
L = L = L = L = O s L F and L O depending on the type of structure (Table 3.2.5.9).
C M W Z c These values can be modified and adapted for specific struc-
t
tures provided that the exposition to lightning effects and the
L T is the typical mean percentage of the economic value probability of damage are considered.
of all goods damaged by electric shock (D1) in case of Section 3.2.5 only defines the loss values. The further proce-
a dangerous event; dure for examining whether protection measures make eco-
L F is the typical mean percentage of the economic value nomic sense is discussed in section 3.2.9.
of all goods damaged by physical damage (D2) in case If the loss of economic value of a structure resulting from a
of a dangerous event; lightning strike also affects surrounding structures or the envi-
L O is the typical mean percentage of the economic value ronment (e.g. in case of chemical or radioactive emissions), the
of all goods damaged by failure of internal systems additional loss due to physical damage (L BE and L VE ) should be
(D3) in case of a dangerous event; taken into account when assessing the total loss (L BT and L VT ):
r t is a factor reducing the loss of animals depending on
the type of ground or floor; L BT = L + L BE
B
r p is a factor reducing the loss due to physical damage
depending on the measures taken to reduce the con- L VT = L + L VE
V
sequences of fire;
r f is a factor reducing the loss due to physical damage L c
depending on the risk of fire or explosion of the struc- L BE = L VE = FE e
ture; c t
c a is the value of the animals in the zone; L FE Loss due to physical damage outside the structure;
c b is the value of the building related to the zone; c e Total value of goods at dangerous locations outside
c c is the value of the content in the zone; the structure.

Type of damage Typical loss value Type of structure
D1: Injuries due to electric shock L T 10 -2 All types
1 Risk of explosion
Hospital, industrial structure, museum, agriculturally
0.5 used plant
D2: Physical damage L F
0.2 Hotel, school, office building, church, building with
entertainment facility, economically used plant
0.1 Others
10 -1 Risk of explosion
Hospital, industrial structure, office building, hotel,
10 -2 economically used plant
D3: Failure of internal systems L O
10 -3 Museum, economically used plant, school, church,
building with entertainment facility
10 -4 Others
Table 3.2.5.9 Type of loss L4: Typical mean values for L T , L F and L O

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