Sound Attenuation
Products
© Pacific HVAC Engineering 2014
www.pacifichvac.com
Tel. Australia 1300 733 833
NZ 0800 100 326
Pacific HVAC Engineering Attenuators
Pacific HVAC Engineering Attenuators
Pacific HVAC Engineering Attenuators offer high performance noise
reduction in ducted ventilation systems at competitive prices.
Construction
Attenuators and pods (where fitted) are rigidly constructed from galvanised
steel, internally lined with sound absorbing material not less than 100mm
thick, retained by galvanised steel perforated sheet.
Attenuator end faces are drilled and tapped to match the flange details of
the associated fan.
Attenuator ‘sound’ absorbing material is chemically inert, non combustible,
non hygroscopic and vermin resistant.
Testing
The performance of Pacific HVAC Engineering Attenuators has been
determined by testing in accordance with BS4718:1971
Ranges Available
•
Circular Un-podded
•
Circular Podded
•
Rectangular Straight
•
Rectangular Tapered
Note: All ranges are available as standard or with Melinex Lining
Suggested Specification
Attenuators shall be designed and
supplied by Pacific HVAC Engineering
Pty Ltd.
Attenuators and pods (where fitted)
shall be rigidly constructed from
galvanised steel, internally lined with
sound absorbing material that is
chemically inert, non combustible,
non hygroscopic, vermin resistant and
retained by galvanised steel
perforated sheet.
Attenuator end faces shall be drilled
and tapped to match the flange
details of the associated fan.
Attenuation Performance
The following tables demonstrate the levels of sound reduction by octave
band to be offset against the sound spectrums of fans.
Published Range
In this catalogue we have published attenuation data relating to un-podded
and podded cylindrical silencers in single as well as double diameter lengths
for the standard range of AX/AT/AC/AY/AZ/AB series axial fans. These data
provide a quick guide for the set of attenuators useful in general
applications.
Selecting Attenuators
To access the full range of attenuators offered by Pacific HVAC Engineering
and to select the right silencer for any given situation, please refer to our
electronic fan and attenuator selection software, FansSelect, available for
download at www.pacificHVAC.com
Your local Pacific HVAC Engineering sales office is equipped to answer
specific queries relating to the full range of silencers and attenuators.
© Pacific HVAC Engineering 2014
www.pacifichvac.com
Tel. Australia 1300 733 833
NZ 0800 100 326
CSU - Standard (un-podded) cylindrical attenuators
Size = 1 x Ø
Sound Power Reduction dB
Code
CSU0400-1D
CSU0450-1D
CSU0500-1D
CSU0560-1D
CSU0630-1D
CSU0710-1D
CSU0800-1D
CSU0900-1D
CSU1000-1D
CSU1120-1D
CSU1250-1D
CSU1400-1D
CSU1500-1D
CSU1600-1D
CSU1800-1D
CSU2000-1D
63
125
250
500
1K
2K
4K
8K
2
2
2
2
3
3
3
3
3
3
3
4
4
4
4
4
3
3
3
3
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
7
7
7
8
8
8
9
9
9
10
10
10
8
8
8
9
11
11
12
12
12
12
12
12
12
12
12
13
11
11
11
11
12
12
11
11
11
10
10
9
9
9
9
9
10
10
10
10
9
8
8
8
7
7
7
7
7
7
7
7
7
7
7
7
7
7
6
6
6
5
5
5
5
5
5
5
7
7
6
6
6
6
5
5
5
5
5
4
4
4
4
4
63
125
250
500
1K
2K
4K
8K
4
4
4
4
6
6
6
6
6
6
6
8
8
8
8
8
5
5
5
5
6
6
6
7
8
8
8
8
8
8
8
8
8
8
8
9
10
10
11
12
13
13
13
14
14
14
14
14
12
13
14
15
18
18
19
19
18
18
18
18
18
19
19
19
18
18
19
19
20
20
19
19
17
17
16
15
15
15
15
14
16
16
15
15
14
13
13
12
12
12
11
10
10
10
10
10
13
12
12
12
11
11
11
10
9
9
8
8
8
8
8
8
10
10
10
10
8
8
8
7
7
7
7
6
6
6
6
6
Size = 2 x Ø
Sound Power Reduction dB
Code
CSU0400-2D
CSU0450-2D
CSU0500-2D
CSU0560-2D
CSU0630-2D
CSU0710-2D
CSU0800-2D
CSU0900-2D
CSU1000-2D
CSU1120-2D
CSU1250-2D
CSU1400-2D
CSU1500-2D
CSU1600-2D
CSU1800-2D
CSU2000-2D
Dimensions 1 x Ø
Dimensions 2 x Ø
Code
CSU0400-1D
A
400
B
606
C
400
D
8
E
M8
F
438
Kg
22.5
Code
CSU0400-2D
A
800
B
606
C
400
D
8
E
M8
F
438
CSU0450-1D
450
656
CSU0500-1D
500
706
450
8
M8
450
24.5
500
12
M8
560
26.8
CSU0450-2D
900
656
CSU0500-2D
1000
706
CSU0560-1D
560
CSU0630-1D
630
766
560
12
M8
620
836
630
12
M8
690
30.5
CSU0560-2D
1120
34.5
CSU0630-2D
1200
CSU0710-1D
710
916
710
16
M10
770
49.5
CSU0710-2D
CSU0800-1D
800
1006
800
16
M10
860
55.3
CSU0900-1D
900
1106
900
16
CSU1000-1D
1000
1206
1000
16
M10
970
M12
1070
CSU1120-1D
1120
1330
1120
20
M12
CSU1250-1D
1250
1456
1250
20
CSU1400-1D
1400
1606
1400
CSU1500-1D
1500
1706
CSU1600-1D
1600
CSU1800-1D
CSU2000-1D
450
8
M8
450
49
500
12
M8
560
53.6
766
560
12
M8
620
61
836
630
12
M8
690
69
1420
916
710
16
M10
770
99
CSU0800-2D
1600
1006
800
16
M10
860
110.6
75
CSU0900-2D
1800
1106
900
16
M10
970
150
91
CSU1000-2D
2000
1206
1000
16
M12
1070
182
1190
103
CSU1120-2D
2240
1330
1120
20
M12
1190
206
M12
1320
111
CSU1250-2D
2400
1456
1250
20
M12
1320
222
20
M12
1470
123
CSU1400-2D
1800
1606
1400
20
M12
1470
246
1500
20
M12
1570
155
CSU1500-2D
3000
1706
1500
20
M12
1570
310
1806
1600
24
M12
1680
197
CSU1600-2D
3200
1806
1600
24
M12
1680
394
1800
2006
1800
24
M12
1880
220
CSU1800-2D
3600
2006
1800
24
M12
1880
440
2000
2206
2000
24
M12
2080
245
CSU2000-2D
4000
2206
2000
24
M12
2080
490
Note: Pressure drop for un-podded attenuators is negligible.
© Pacific HVAC Engineering 2014
www.pacifichvac.com
Tel. Australia 1300 733 833
NZ 0800 100 326
Kg
45
CSP - Podded cylindrical attenuators
Size = 1 x Ø
Sound Power Reduction dB
Code
CSP0400-1D
CSP0450-1D
CSP0500-1D
CSP0560-1D
CSP0630-1D
CSP0710-1D
CSP0800-1D
CSP0900-1D
CSP1000-1D
CSP1120-1D
CSP1250-1D
CSP1400-1D
CSP1500-1D
CSP1600-1D
CSP1800-1D
CSP2000-1D
63
125
250
500
1K
2K
4K
8K
4
4
4
4
4
4
4
4
4
4
4
6
6
6
6
6
5
5
5
6
6
6
6
7
7
7
7
9
9
9
10
10
8
8
9
9
9
10
10
10
12
12
12
13
13
13
14
14
14
14
14
15
17
17
18
18
20
20
20
21
22
22
22
23
19
19
19
20
22
22
21
20
18
18
18
18
17
17
17
17
18
18
17
17
18
18
18
18
15
14
14
13
13
13
13
12
14
14
14
14
15
15
15
15
13
13
13
11
10
10
10
10
11
11
11
11
10
10
10
11
11
11
11
10
9
9
9
9
63
125
250
500
1K
2K
4K
8K
7
7
7
7
7
7
7
7
7
7
7
10
10
10
10
10
9
9
9
10
10
10
11
11
12
13
13
15
15
15
16
16
13
14
14
14
15
15
16
16
18
19
19
21
21
21
22
22
24
24
25
25
28
28
29
30
31
31
31
28
29
29
29
29
29
29
30
31
34
33
32
32
29
29
29
25
24
24
24
24
28
28
27
27
29
29
29
29
25
24
24
21
21
20
20
19
23
24
24
24
26
26
25
25
21
20
20
17
16
16
16
16
19
19
20
20
19
19
18
18
17
17
17
15
15
15
15
14
Size = 2 x Ø
Sound Power Reduction dB
Code
CSP0400-2D
CSP0450-2D
CSP0500-2D
CSP0560-2D
CSP0630-2D
CSP0710-2D
CSP0800-2D
CSP0900-2D
CSP1000-2D
CSP1120-2D
CSP1250-2D
CSP1400-2D
CSP1500-2D
CSP1600-2D
CSP1800-2D
CSP2000-2D
Dimensions 1 x Ø
Dimensions 2 x Ø
Code
CSP0400-1D
A
B
C
D
E
F
400
606
400
8
M8
438
CSP0450-1D
450
656
450
8
M8
CSP0500-1D
500
706
500
12
M8
CSP0560-1D
560
766
560
12
CSP0630-1D
630
836
630
CSP0710-1D
710
916
710
CSP0800-1D
800
1006
CSP0900-1D
900
CSP1000-1D
1000
CSP1120-1D
Kg
Z
25.3
8.2
Code
CSP0400-2D
A
800
B
606
C
400
D
8
E
M8
F
438
Kg
50.6
Z
8.2
450
33
6.2
560
36.5
4
CSP0450-2D
900
656
CSP0500-2D
1000
706
450
8
M8
450
66
6.2
500
12
M8
560
73
M8
620
41.5
2.7
CSP0560-2D
1120
4
766
560
12
M8
620
83
2.7
12
M8
690
16
M10
770
47.5
1.5
CSP0630-2D
71
0.9
CSP0710-2D
1200
836
630
12
M8
690
95
1.5
1420
916
710
16
M10
770
142
800
16
M10
860
79
0.55
0.9
CSP0800-2D
1600
1006
800
16
M10
860
158
0.55
1106
900
16
1206
1000
16
M10
970
108
M12
1070
129
0.31
CSP0900-2D
1800
1106
900
16
M10
970
216
0.31
0.22
CSP1000-2D
2000
1206
1000
16
M12
1070
258
1120
1330
1120
20
M12
1190
145
0.22
0.13
CSP1120-2D
2240
1330
1120
20
M12
1190
290
CSP1250-1D
1250
1456
1250
20
M12
0.13
1320
160 0.081
CSP1250-2D
2400
1456
1250
20
M12
1320
320 0.081
CSP1400-1D
1400
CSP1500-1D
1500
1606
1400
20
1706
1500
20
M12
1470
180 0.052
CSP1400-2D
1800
1606
1400
20
M12
1470
360 0.052
M12
1570
250
0.04
CSP1500-2D
3000
1706
1500
20
M12
1570
CSP1600-1D
1600
1806
1600
500
24
M12
1680
290 0.031
CSP1600-2D
3200
1806
1600
24
M12
1680
580 0.031
CSP1800-1D
1800
2006
CSP2000-1D
2000
2206
1800
24
M12
1880
325 0.017
CSP1800-2D
3600
2006
1800
24
M12
1880
650 0.017
2000
24
M12
2080
362 0.013
CSP2000-2D
4000
2206
2000
24
M12
2080
724 0.013
Note: Air pressure drop of attenuator (Pa) = Z x
Q = volume flow (m3/s)
Q2
where Z = factor listed in tables above and
© Pacific HVAC Engineering 2014
www.pacifichvac.com
Tel. Australia 1300 733 833
NZ 0800 100 326
0.04
LDC Series - cylindrical silencers
LDC Series
LDC - silencers are high quality, rigid metal tubular design attenuators for use
with small diameter ventilation systems. Silencers can be fitted to the inlet /
outlet of circular duct fans or to grilles and louvres as required.
Construction
Silencers are manufactured from galvanised steel with high performance
acoustic lining / absorbing material. The sound absorbing material is
chemically inert, non hygroscopic and vermin resistant.
Features
Long spigots for easier connection to fans, grilles or louvres.
Suitable for rigid or flexible duct systems
Part
A
B
C
kg
LDC150-600
150
250
600
5.3
LDC200-600
200
300
600
6.9
LDC200-900
200
300
900
9.7
LDC250-900
250
355
900
8.5
LDC315-600
315
415
600
11.8
LDC315-900
315
415
900
16.3
Sound Power Reduction dB(A)
Part
63
125
250
500
1K
2K
4K
8K
LDC150-600
5
10
19
24
34
32
20
LDC200-600
4
9
17
22
29
25
18
LDC200-900
7
13
24
31
44
31
20
LDC250-900
6
11
21
27
39
25
19
LDC315-600
2
6
11
14
9
4
5
LDC315-900
3
7
16
22
12
6
7
Suggested Specification
Rigid Cylindrical Silencers shall be of
the LDC Series supplied by Pacific
HVAC Engineering Pty Ltd.
Silencers shall be constructed from
aluminium and galvanised steel.
Internal sound absorbing material shall
be chemically inert, non combustible,
non hygroscopic and vermin resistant.
Acoustic performance shall be
determined by testing in accordance
with BS4718:1971
© Pacific HVAC Engineering 2014
www.pacifichvac.com
Tel. Australia 1300 733 833
NZ 0800 100 326
LFS Series - lightweight flexible silencers
LFS Series
LFS - Lightweight Flexible Silencers provide an economically priced solution to
excessive noise within ducted systems. Silencers can be fitted to the inlet /
outlet of circular duct fans or to grilles and louvres as required. The silencers
may be bent to a maximum radius of 2 x overall (B) diameter with negligible
effect on insertion loss values.
In combination with MFP Series mixed flow fans, LFS silencers offer very low
noise ventilation performance in offices, residential dwellings and
commercial / retail spaces.
All components of the kits have been designed to be as light as possible for
fast installation and safe handling in tight spaces.
Construction
Silencers are manufactured from spun aluminium (spigots), metallised
polyester with helical steel support (outer case) and high performance
acoustic lining / absorbing material. The sound absorbing material is
chemically inert, non hygroscopic and vermin resistant.
Features
Ultra light weight.
Class leading acoustic performance.
Long spigots for easier connection to fans, grilles or louvres.
Economically priced.
Flexibility allows installation in tight locations
Suitable for rigid or flexible duct systems
LFS Silencer
Part
A
B
C
kg
LFS150-S
150
265
600
1.7
LFS200-S
200
320
600
1.9
LFS200-L
200
320
1100
3.8
LFS250-S
250
365
600
2
LFS250-L
250
365
1100
4
LFS315-S
315
415
1100
4.2
LFS315-L
315
415
1600
6.3
Suggested Specification
Lightweight Silencers shall be of the
LFS Series manufactured by Pacific
HVAC Engineering Pty Ltd.
Silencers shall be constructed from
aluminium, metallised polyester
supported by helical steel wire.
Internal acoustic lining and sound
absorbing material shall be chemically
inert, non combustible, non
hygroscopic and vermin resistant.
Acoustic performance shall be
determined by testing in accordance
with BS4718:1971
Sound Power Reduction dB(A)
Part
63
125
250
500
1K
2K
4K
8K
LFS150-S
6
9
12
32
40
40
23
20
LFS200-S
2
5
12
20
38
22
16
13
LFS200-L
7
8
12
22
47
35
20
14
LFS250-S
2
3
8
16
29
16
13
10
LFS250-L
5
6
13
21
43
23
11
12
LFS315-S
4
5
11
21
38
17
8
10
LFS315-L
6
7
17
34
46
24
14
18
© Pacific HVAC Engineering 2014
www.pacifichvac.com
Tel. Australia 1300 733 833
NZ 0800 100 326
© Pacific HVAC Engineering 2014
www.pacifichvac.com
Tel. Australia 1300 733 833
NZ 0800 100 326