APPENDIX B - PRACTICAL PIPE DESIGNS for ASPIRATING SYSTEMS
The following tables show some typical EN54
compliant pipe designs for FAAST LT-200
devices with different overall pipe lengths.
Each design has a one size sample hole for
ease of installing and testing the system.
No exhaust pipe has been included in these
designs.
In all the suggested layouts, the sample hole
spacing is set to 10m between holes, which
is the recommended arrangement for point
smoke detectors in the UK (BS 5839). Air
flow through the detector has been kept at, or
above, 39 l/min for best performance.
In the designs with non-sensing end holes,
the distance to the first hole is 9m and the
end hole is 1m from the last sample hole.
N200-102-01
CLASS C PIPE DESIGNS WITH SINGLE SAMPLE HOLE/END HOLE SIZE AND 10m SPACING
Pipe
Number
Hole
Length
of holes
size
(m)
(mm) (mm) (I/min)
100
10
3
90
9
3
80
8
3.5
70
7
3.5
60
6
4
50
5
4.5
40
4
4.5
30
3
5
20
2
5.5
10
1
6.5
* Non‐sensing end hole
CLASS C PIPE DESIGNS WITH SINGLE SAMPLE HOLE/END HOLE SIZE AND 10m SPACING
Per pipe
Number
Hole
length
of holes
size
(m)
(mm) (mm) (I/min)
80
8
2.5
70
7
2.5
60
6
3
50
5
3
40
4
3.5
30
3
3.5
20
2
4
10
1
5
* Non‐sensing end hole
CLASS C PIPE DESIGNS WITH SINGLE SAMPLE HOLE SIZE (Inc. SAMPLING END HOLE)
Pipe
Number
Hole
Length
of holes
size
(m)
(mm) (I/min)
100
X
‐
90
X
‐
80
8
3.5
70
7
4
60
6
4.5
50
5
5.5
40
4
6
30
3
6.5
20
2
6.5
10
X
‐
X: No adequate or recommended single sample hole size design
12
1 PIPE
End
Air
Flow
hole*
flow
balance
3
40
0.5
3
39
0.53
3.5
43
0.52
3.5
42
0.62
4
45
0.6
4.5
45
0.62
4.5
45
0.76
5
46
0.83
5.5
45
0.92
6.5
45
1
2 PIPE (T FORM)
End
Air
Flow
hole*
flow
balance
2.5
47
0.71
2.5
45
0.77
3
46
0.72
3
45
0.81
3.5
45
0.81
3.5
44
0.91
4
44
0.95
5
45
1
AND 10m SPACING ‐ 1 PIPE
Air
Flow
Average
flow
balance
sensitivity
(%/m)
‐
‐
‐
‐
42
0.6
0.79
44
0.58
0.70
44
0.59
1.00
45
0.54
0.86
44
0.65
0.67
45
0.78
0.99
44
0.92
1.31
‐
‐
Average
Alarm
Fan Total hole
sensitivity
level
(%/m)
0.74
1
10
0.66
1
10
0.91
2
10
0.79
2
10
1.14
3
10
0.98
3
9
0.80
3
10
1.29
4
10
0.97
4
10
1.31
5
10
Average
Alarm
Fan Total hole
sensitivity
level
(%/m)
1.16
1
8
1.03
1
8
0.91
1
5
1.16
2
6
0.97
2
4
1.30
3
6
0.98
3
6
1.31
4
5
Alarm
Fan
level
hole area
‐
‐
‐
‐
‐
‐
2
10
2
10
3
9
3
8
3
8
4
8
5
10
‐
‐
‐
I56-6577-008
area
(mm
2
)
77.76
70.70
86.60
76.98
87.98
95.44
79.53
78.55
71.28
66.37
area
2
(mm
)
83.46
73.64
91.90
77.76
86.60
67.36
62.84
58.91
Total
(mm
2
)
‐
‐
76.98
87.98
95.44
118.81
113.11
99.56
66.37
‐