Noise from ventilation systems

To ensure good acoustic conditions the average A-weighted sound pressure level in noise sensitive rooms, such as bedrooms and living rooms, should not exceed 30 dB LAeq,T (see paragraph 2.38). In less sensitive rooms, such as kitchens and bathrooms, a higher level would be acceptable (e.g. 35 dB LAeq,T). Noise from a continuously running mechanical ventilation system on its minimum low rate should not normally exceed these levels, and should preferably be lower in order to minimise the impact of the ventilation system.