a Amortization rate............................................................................ Annex E
Ad Collection area for flashes to an isolated structure ................................... A.2
Ad¢ Collection area attributed to an elevated roof protrusion ......................... A.2.1
Ai Collection area for flashes near a service................................. A.4; Table A.3
Al Collection area for flashes to a service.................................... A.4; Table A.3
Am Area of influence for flashes near a structure............................................ A.3
B Building............................................................................................... A.2
c Mean value of possible loss of the structure, in currency ................... C.4; C.5
Cd Location factor...................................................................... A.2; Table A.2
Ce Environmental
factor.............................................................. A.5;
Table A.5
CL Annual cost of total loss in absence of protection measures.......... 5.6; Annex E
CRL Annual cost of residual loss....................................................... 5.6; Annex E
CP Cost of protection measures............................................................ Annex E
CPM Annual cost of selected protection measures............................... 5.6; Annex E
Ct Correction factor for a HV/LV transformer on the service............ A.4;Table A.4
cA Value of the animals in the zone, in currency........................................... C.5
cB Value of the building relevant to the zone, in currency.............................. C.5
cC Value of the content in the zone, in currency............................................ C.5
cS Value of the internal systems (including their activities) in the zone, in currency.......................................................................................................... C.5
ct Total value of the structure, in currency........................................... C.4; C.5
cZ Value of the cultural heritage in the zone, in currency............................... C.4
Di Lateral distance relevant to lightning flash near a service ......................... A.5
D1 Injury to living beings.......................................................................... 4.1.2
D2 Physical damage ................................................................................ 4.1.2
D3 Failure of electrical and electronic systems............................................ 4.1.2
hz Factor increasing the loss when a special hazard is present......... C.2;Table C.5
H Height of the structure ........................................................................... A.4
Ha Height of the structure connected at end “a” of a service ........................... A.4
Hb Height of the structure connected at end “b” of a service............................ A.4
Hc Height of the service conductors above ground......................................... A.4
i Interest rate................................................................................... Annex E
KMS Factor relevant to the performance of protection measures against LEMP.... B.4
Kp KS1 Factor relevant to the screening effectiveness of the structure................... B.4
KS2 Factor relevant to the screening effectiveness of shields internal to the structure .... B.4
KS3 Factor relevant to the characteristics of internal wiring.............................. B.4
KS4 Factor relevant to the impulse withstand voltage of a system...................... B.4
L Length of structure................................................................................ A.2
LB Loss in a structure related to physical damage (flashes to structure) 6.2; Table 8
Lc Length of service section....................................................................... A.4
LC Loss related to failure of internal systems (flashes to structure)..... 6.2; Table 8
Lf Loss in a structure due to physical damage.............................................. C.1
LM Loss related to failure of internal systems (flashes near structure).. 6.3; Table 8
Lo Loss in a structure due to failure of internal systems................................. C.1
Lt Loss due to injury by touch and step voltages .......................................... C.1
LU Loss related to injury of living beings (flashes to service).............. 6.4; Table 8
LV Loss in a structure due to physical damage (flashes to service)...... 6.4; Table 8
LW Loss related to failure of internal systems (flashes to service)........ 6.4; Table 8
LX Consequent loss in a structure................................................................ 6.1
LZ Loss related to failure of internal systems (flashes near a service). 6.5; Table 8
L1 Loss of human life in a structure........................................................... 4.1.3
L2 Loss of service to the public in a structure............................................. 4.1.3
L3 Loss of cultural heritage in a structure................................................... 4.1.3
L4 Loss of economic value in a structure.................................................... 4.1.3
m Maintenance rate............................................................................ Annex E
m* is the collection coefficient ................................................ Annex a,table A.0
NX Number of dangerous events per annum................................................... 6.1
ND Number of dangerous events due to flashes to a structure....................... A.2.3
NDa Number of dangerous events due to flashes to a structure at
“a” end of line ...................................................................... A.2.4; Table 8
Ng Lightning ground flash density................................................................ A.1
NI Number of dangerous events due to flashes near a service........................ A.5
NL Number of dangerous events due to flashes to a service........................... A.4
NM Number of dangerous events due to flashes near a structure...................... A.3
nz Number of possible endangered persons (victims or users not served) C.2; C.3; E.2
ns Estimated or measured annual number of switching overvoltages......... Annex D
Ns Annual number of switching overvoltages in excess of 2,5 kV.............. Annex D
nt Expected total number of persons (or users served)in the structure...... C.2; C.3
P Probability of damage........................................................................ 3.1.29
PA Probability of injury to living beings (flashes to a structure)........... 6.2; Table 8
PB Probability of physical damage to a structure (flashes to a structure) 6.2; Table 8
PC Probability of failure of internal systems (flashes to a structure)..... 6.2; Table 8
PLD Probability of failure of internal
systems (flashes to a connected service)....... B.5;
B.6; B.7
PLI Probability of failure of internal
systems (flashes near a connected service)................. B.8
PM Probability of failure of internal systems (flashes near a structure). 6.3; Table 8
PMS Probability of failure of internal systems (with protection measures)............ B.4
PSPD Probability of failure of internal systems or a service when SPDs
are installed................................................................................... B.3;B.4
PU Probability of injury to living beings (flashes to a connected service).... 6.4; Table 8
PV Probability of physical damage to a structure
(flashes to a connected service)....................................................... 6.4; Table 8
PW Probability of failure of internal systems (flashes to a connected service) 6.4; Table 8
PX Probability of damage to a structure......................................................... 6.1
PZ Probability of failure of internal systems
(flashes near a connected service).............................................. 6.5; Table 8
ra Reduction factor associated with the type of surface................................. C.2
rp Factor reducing the loss due to provisions against fire.............................. C.2
R Risk ................................................................................................ 3.1.32
RA Risk component (injury to living beings – flashes to a structure)............... 4.2.2
RB Risk component (physical damage to a structure – flashes to a structure). 4.2.2
RC Risk component (failure of internal systems -flashes to a structure).......... 4.2.2
RD Risk for a structure due to flashes to the structure.................................. 4.3.1
rf Factor reducing loss depending on risk of fire........................................... C.2
RF Risk due to physical damage to a structure............................................ 4.3.2
RI Risk for a structure due to flashes not striking the structure.................... 4.3.1
RM Risk component (failure of internal systems – flashes near a structure). 4.2.3
R¢M Risk RM when protection measures are adopted................................. Annex E
RO Risk due to failure of internal systems.................................................. 4.3.2
Rs Shield resistance per unit length of a cable......................................... B.5;B.8
RS Risk due to injury to living beings........................................................ 4.3.2
RT Tolerable risk.................................................................................... 3.1.34
RU Risk component (injury to living being – flashes to a connected service)... 4.2.4
RV Risk component (physical damage to structure
– flashes to a connected service)......................................................... 4.2.4
RW Risk component
(failure of internal
systems – flashes to the connected service)...... 4.2.4
RX Risk component for a structure........................................................... 3.1.33
RZ Risk component (failure of internal systems – flashes near a service)....... 4.2.5
R1 Risk of loss of human life in a structure........................................... 4.2.1; 4.3
R2 Risk of loss of service to the public in a structure............................ 4.2.1; 4.3
R3 Risk of loss of cultural heritage in a structure.................................. 4.2.1; 4.3
R4 Risk of loss of economic value in a structure................................... 4.2.1; 4.3
S Structure.............................................................................................. A.2
S......... Annual saving of money.................................................................. Annex E
SS Section of a service........................................................................... 3.1.36
S1 Source of damage - Flashes to a structure............................................. 4.1.1
S2 Source of damage - Flashes near a structure.......................................... 4.1.1
S3 Source of damage - Flashes to a service............................................... 4.1.1
S4 Source of damage - Flashes near a service............................................ 4.1.1
tz Annual period of loss of service, in hours................................................. C.3
tp Time in hours per year that persons are present in a dangerous place......... C.2
Td Thunderstorm days per year................................................................... A.1
UW Rated impulse withstand voltage of a system............................................ B.4
w Mesh width........................................................................................... B.4
W Width of structure.................................................................................. A.2
Wa Width of the structure connected at end “a” of a service ............................ A.4
ZS Zones of a structure........................................................................... 3.1.35