Planning
Defining the place of installation
4
34 | 66
Building Technologies
007011_m_en_--
Fire Safety
2018-06-28
Example of how to calculate the maximum detection distance
Calculate the maximum detection distance for a heptane fire, 0.1 m
2
in size. The
flame detector has a 'Normal' detector sensitivity and a vision angle of 0°.
Known:
S Correction coefficient for detector sensitivity
23
Gg Fire size wanted
0.1 m
2
Gb Basic fire size
0.25 m
2
K Correction coefficient for directional sensitivity
1
F Correction coefficient for fuel
1.5
The maximum detection distance is 21 m.
4.2.2 Calculate mounting height
In order to calculate the maximum mounting height h, you need to know detection
distance d.
Formula for calculating maximum mounting height h
h Mounting height
d Detection distance
Example of how to calculate the maximum mounting height
Calculate the maximum mounting height given a detection distance of 21 m.
Known:
Detection distance d = 21 m
The maximum mounting height is 12 m.
d =
F
K
S
Gb
Gg
´
´
´
= 23 m
´
1
´
1.5 = 21.82 m
´
0.25 m
2
0.1 m
2
h =
3
d
