EAR42W: Fresh air in or out – no noise.

One of the best performing acoustic vents available in the UK. Provides an outstanding Dn,e,w; 42dB(A) for areas with high external noise transmission. Humidity control to regulate supply of fresh air effectively throughout the day in response to changing indoor humidity levels.


  • Bottom operation only.
  • Provides up to 3912mm² equivalent area.
  • Upward air deflection to eliminate draughts.
  • May require add-on section in some installations.

Noise guidance covers three specific areas;

  • Planning permission
  • Internal noise levels
  • Ventilation system noise levels

All three are relevant to ventilation as all systems require external penetrations in the façade of the building which can allow noise transfer.

Sound can be measured in two ways:

  • Intensity/loudness of sound is measured in decibels (dB).
  • Pitch of sound is measured in frequency of vibrations per second.

The decibel scale runs from the faintest sound the human ear can detect (0dB) to over 180dB that is similar to the noise a rocket creates during a launch.

Acoustic ventilation solutions from Greenwood have been independently tested to the latest test standard: BS EN ISO 717-1: 1997 and include varying performance at different frequencies, e.g. pink noise/white noise.

Acoustic Vents Diagram
EAR42W Air Flow Diagram

Click Below for Size Diagram.

EAR42W Vents Dimensions

Acoustic Performance

  • Dn,e,w: = 42dB(A)
  • Dn,e,w: (C) = 42dB
  • Dn,e,w: (Ctr) = 42dB
  • Dn,e,w: Average weighted performance across frequency range
  • C: Pink noise
  • Ctr: Road noise

Ordering Information

WordPress Table