The air handling unit is designed so that the A-weighted emission sound pressure level at the operating position, i.e. in the area intended for normal operation and service access at the unit switchboard, does not exceed 70 dB(A). The specific value is determined by the specific configuration of the unit, the selected operating point and the operating conditions stated in the technical specification of the given unit.
Compliance with this requirement is verified in the manufacturer’s design software. If the calculated value of the sound pressure emitted through the unit casing at the operating position exceeds 70 dB(A), such a unit configuration is not released for production without a change to the unit design.
The stated value applies to the noise emissions of the unit itself under the specified operating conditions and does not include the effect of other noise sources at the place of installation or the effect of the specific acoustic properties of the machine room or surrounding area.