NCF
EN
14
2.6
Noise emission risks
WARNING!
Risk of personal injury.
•
Vibrations and noise emission are directly correlated. Compliance with the instructions
given for correct installation so as to reduce vibrations to a minimum is of equivalent
importance for noise reduction.
•
Avoid positioning fans in areas that could increase the noise risk.
•
Avoid working positions that increase the noise risk for operatives.
•
Reducing exposure times and the use of Personal Protection Equipment will reduce the
risks caused by exposure to noise emissions. See Figure 1.
•
With sound pressures higher than 100 dBA, operatives may approach the fan only if it is
not operating, even if wearing Personal Protection Equipment.
Since the noise emitted by a fan can be influenced by external factors that can affect the
overall noise level, such as:
•
The dimensions of the environment in which the fan is installed.
•
The presence of static elements near the fan (e.g. walls).
•
The presence of other machines that are also sources of noise emission.
Nederman invites the user to measure ambient noise levels. It should be noted that
the presence of other operating machines generates a “superimposition of effects” and
resonance that multiply ambient noise.
In addition, in cases of restricted environments, or if the fan is installed against walls, the
effect of reverberation and resonance on structures (walls and ceiling) is “exponential”.
The definition of the risks to workers of exposure to noise is not the responsibility of
Nederman, which limits itself to indications of values, levels of uncertainty, standards or
criteria used for noise emission measurements.
As envisaged by applicable legislation, it is the user that must assess the level of exposure
of operatives to noise emissions using its own specific procedures, identifying:
•
Sources of noise and their relative importance.
•
Average exposure times for each operative.
•
The level of direct and reflected noise.
•
The noise transmitted by structures and not through the air.
If exposure to noise, in terms of sound pressure, exceeds 80 dBA, the employer must
provide operatives with PPE for the hearing, such as earplugs or earmuffs. If exposure is
equal to or higher than 85 dBA, the employer must take all possible action to ensure that
PPE for the hearing is effectively used.
3
Description
3.1
Intended use
The NCF fan is a centrifugal fan designed for use in all types of industrial process and
ventilation systems, mounted indoor as well as outdoor.
The fan must be used in the flow range specified in the performance diagrams. Use of the
fan with flows lower than the minimum value indicated in the diagrams may cause unstable
fluid dynamic operation and vibrations.
