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ARTUS™ Technical Manual 9690348 v3_04_2020
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Maximum Acoustic Criteria
The following criteria are taken from the British Council of Offices: 2014 Guide to Specification, with a relaxation in the
case of variable speed air conditioning systems of up to 5dB.
Open plan office: NR40+5 = NR45.
Cellular office: NR35+5 = NR40.
Minimum Acoustic Criteria
In order to achieve privacy in open plan offices, a minimum level of masking noise may be required. In BS 8233:2014
Guidance on sound insulation and noise reduction for buildings this is recommended to be in the range of NR25 to
NR34 depending on the contribution from external noise.
The Artus unit has the option of a control function that sets a minimum fan speed that will provide useful sound masking
if desired, for an open plan office.
Quick Selection - Section C - Acoustics
Commercial Office with False Ceiling
Graph 13 - Commercial Office with False Ceiling - Supply Airflow vs. Calculated Noise Rating
0
5
10
15
20
25
30
35
40
45
50
55
0
20
40
60
80
100
120
140
160
C
al
cu
lat
ed
N
R
Supply Airflow (l/s)
In ceiling, open
plan, one Artus
per 20.25m²
zone
In ceiling, open
plan, one Artus
per 27m² zone
In ceiling, open
plan, one Artus
per 40.5m² zone
In ceiling, open
plan, one Artus
per 13.5m² zone
Description Zone Type
Zone
Dimensions
Max kW
each
Cooling
load
W/m
2
Supply
airflow,
l/s
Calc NR
Finishes
Ceiling Sound
Insulation
Mid-
frequency
reverberation
time
In ceiling,
open plan,
one Artus per
27m² zone
Perimeter 6m x 4.5m
27m²
2.35
87
130
NR 40
Carpet,
plaster walls,
absorbing
ceiling
Metal
perforated tile
ceiling (Rw7)
0.8s
In ceiling,
open plan,
one Artus per
20.25m² zone
Perimeter 4.5m x 4.5m
20.25m²
1.76
87
98
NR 35
As above
As above
0.8s
In ceiling,
cellular, one
Artus per
13.5m² zone
Cellular
3m x 4.5m
13.5m²
1.17
87
65
NR 26
As above
As above
0.5s
In ceiling,
open plan,
one Artus per
40.5m² zone
Internal
9m x 4.5m
40.5m²
1.78
44
99
NR 33
As above
As above
0.8s
Comfort
ARTUS™
