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r p is a factor reducing the loss due to physical damage L F is the typical mean percentage of the value of all
depending on the measures taken to reduce the con- goods damaged by physical damage (D2) in case of a
sequences of fire; dangerous event;
r f is a factor reducing the loss due to physical damage r p is a factor reducing the loss due to physical damage
depending on the risk of fire or explosion of the struc- depending on the measures taken to reduce the con-
ture; sequences of fire;
n z is the number of served users in the zone; r f is a factor reducing the loss due to physical damage de-
pending on the risk of fire or explosion of the structure;
n t is the total number of served users in the structure.
c z is the value of the cultural heritage in the zone;
IEC 62305-2 (EN 62305-2) specifies typical mean values for L F
and L 0 depending on the type of service (Table 3.2.5.6). These c t is the total value of the building and content of the
structure (sum of all zones).
values also provide information on the significance of the type
of service to the public. If required, they can be modified and IEC 62305-2 (EN 62305-2) specifies a typical mean value for
adapted for specific structures provided that the exposition to L F (Table 3.2.5.7). This value can be modified and adapted
lightning effects and deviating significances are considered. for specific structures provided that the exposition to lightning
effects is considered.
Loss of cultural heritage (L3) Loss of economic value
Loss of cultural heritage is defined by the properties of the Loss of economic value is also defined by the properties of the
structure or its zones. These properties are described by means zone which are described by means of reduction factors (r t , r p , r f ).
of reduction factors (r p , r f ). Moreover, the relation between the Moreover, the relation between the decisive value in the zone
value of the zone (c z ) and the total value (building and con- and the total value (c t ) of the entire structure is required to
tent) of the entire structure (c t ) is important. There are two assess the damage in a zone.
loss values:
The total value of a structure may include animals, buildings,
r r L c contents and internal systems including their activities. The de-
L = L = p f F Z cisive value depends on the type of damage (Table 3.2.5.8).
B V c
t Thus, there are up to eight loss values:

Type of damage Typical loss value Type of service
10 -1 Gas, water, power supply
D2: Physical damage L F
10 -2 TV, telecommunication
10 -2 Gas, water, power supply
D3: Failure of internal systems L O
10 -3 TV, telecommunication
Table 3.2.5.6 Type of loss L2: Typical mean values for L F and L O

Type of damage Typical loss value Type of service
D2: Physical damage L F 10 -1 Museum, gallery
Table 3.2.5.7 Type of loss L3: Typical mean values for L F

Type of damage Meaning Value Meaning
Injury of animals due to
D1 c a Value of animals
electric shock
D2 Physical damage c a + c b + c c + c s Value of all goods
D3 Failure of internal systems c s Value of internal systems and their activities
Table 3.2.5.8 Type of loss L4: Relevant values depending on the type of loss

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