Equivalent area
Domestic Ventilation Compliance Guide, 2010 Edition (with 2011 amendments), published by the Department for Communities and Local Government in July 2011, suggests that equivalent area is: ‘…a measure of the aerodynamic performance of a ventilator. It is the area of a sharp-edged circular orifice which air would pass through at the same volume flow rate, under an identical applied pressure difference, as the opening under consideration.’
Approved Document O: Overheating, published by HM Government in 2021, defines equivalent area as: ‘A measure of the aerodynamic performance of an opening. It is the area of a sharp-edged circular orifice through which air would pass at the same volume flow rate, under an identical applied pressure difference, as through the opening under consideration.’
The equivalent area of a background ventilator is determined at 1Pa pressure difference in accordance with Table 1.7 of Approved document F: Volume 1: Dwellings, 2021 edition.
See also: Effective area and Discharge coefficients, free, effective and equivalent areas
[edit] Related articles on Designing Buildings
- Air change rates.
- Approved Document F.
- Background ventilator.
- Cross ventilation.
- Discharge coefficients, free, effective and equivalent areas
- Displacement ventilation.
- Effective area.
- Free area.
- Heat recovery ventilation.
- Mechanical ventilation.
- Natural ventilation.
- Stack effect.
- Thermal comfort.
- Underfloor air distribution.
- Ventilation.
- Whole building ventilation.
Discharge coefficients, free, effective and equivalent areas
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