Table des Matières
Publicité
Les langues disponibles
Les langues disponibles
3. SAFETY
Noise level
When pump noise level exceeds 85dBA attention must be given to prevailing Health and
Safety Legislation, to limit the exposure of plant operating personnel to the noise. The
usual approach is to control exposure time to the noise or to enclose the machine to re-
duce emitted sound. If no noise requirements were defined then machines above a certain
power level will exceed 85 dB(A). In such situations consideration must be given to the
fitting of an acoustic enclosure to meet local regulations.
Pump noise level is dependent on a number of factors - the type of motor fitted, the operat-
ing capacity, pipework design and acoustic characteristics of the building. Typical sound
pressure levels measured in dB and A-weighted are shown in the table below.
The figures are indicative only, they are subject to a +3 dB tolerance, and cannot be guaranteed.
The values are based on the noisiest ungeared electric motors which are likely to be encountered. They are LpA
sound pressure levels at 1m (3.3ft) from the directly driven pump, for "free field over a reflecting plane".
If a pump only has been purchased, for fitting with your own driver, then the "pump only" noise levels from the table
should be combined with the level for the driver obtained from the supplier. If the motor is driven by an inverter, it
may show an increase in noise level at some speeds. Consult a Noise Specialist for this calculation
In areas where the staff has to intervene, remember that when the level of the sound pressure is:
• Below 70 dBA :It is not necessary to take special precautions.
• Above 70 dBA :People working continuously in the machine room must be supplied with protective devices
against noise.
• Below 85 dBA :No particular measures need to be taken for casual visitors staying in the room during a limited
period.
• Above 85 dBA :The room must be considered as a dangerous area because of the noise and a warning sign
must be fixed at each entry warning the people coming into the room, even for a short period, that they must
wear hearing protection.
• Above 105 dBA: Special hearing protection adapted to this noise level and to the spectral noise components
must be installed and a warning sign to this effect erected at each entry. The staff in the room must wear ear
protection.
Make sure that the noise, which travels through the walls and windows, does not generate too high noise levels
in the machine room's surroundings.
HP - HPM
25
HV - HVM
HP - HPM - HPR
32
HV - HVM
HP - HPM - HPR
50
HV - HVM
HP - HPM - HPR
80
HV - HVM
HP - HPM - HPR
100
HV - HVM
HP - HPM - HPR
125
HV - HVM
HP - HPM - HPR
150
HV - HVM
HP - HPM
250
LpA [dB] pump only
3500 rpm 2950 rpm 1750 rpm 1450 rpm 3500 rpm 2950 rpm 1750 rpm 1450 rpm
<=88
<=84
<=77
92
88
79
101
97
84
111
107
90
100
13
LwA [dB] pump + motor
<=75
<=102
<=100
76
102
100
80
104
102
84
106
104
95
<=92
<=89
93
91
96
95
100
99
118
112
Publicité
Table des Matières
