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BEAM PLUS FOR EXISTING BUILDINGS INDOOR ENVIRONMENTAL QUALITY (IEQ)
V ERSION 1.2 IEQ 12 L OCALISED V ENTILATION
Copyright © 2012 BEAM Society Limited. All rights reserved.
Page 128
6 IEQ 6.4 VENTILATION
IEQ 12 LOCALISED VENTILATION
EXCLUSIONS None.
OBJECTIVE Prevent exposure of building occupants to concentrated indoor sources
of pollutants.
CREDITS ATTAINABLE 1
PREREQUISITES Compliance with CAP 123J Building (Ventilating Systems) Regulations.
CREDIT REQUIREMENT 1 credit for the provision of an adequate ventilation system for
rooms/areas where significant indoor pollution sources are generated.
ASSESSMENT The Client shall provide evidence in the form of a report prepared by a
suitably qualified person detailing the design criteria that have been
adopted and details of the ventilation system providing for local exhaust
where concentrated pollutant sources are likely to be present. The report
shall provide details of tests and the results demonstrating that the
design performance is achieved. Where the design ventilation rate
specified is lower than that specified in a recognised international or
national standard the client shall demonstrate through appropriate testing
that there is 99% isolation between areas with concentrated pollutant
sources and occupied areas.
BACKGROUND Concentrated pollution sources are best managed at source. The
provision of localised ventilation, segregated from the general ventilation,
is an appropriate strategy. In commercial and similar premises sources
such as photocopying equipment, smoking lounges, etc. should be
provided with dedicated exhaust systems. In other buildings local
exhaust is intended to remove contaminants from specific rooms such as
kitchens, in which concentrated sources are expected.
DOMESTIC KITCHENS PNAP No. APP-130 [1] specifies performance based criteria for kitchen
ventilation as an alternative means of satisfying Building (Planning)
Regulations (B(P)Reg.) 30, 31 and 32. These criteria are 1.5 Ach under
natural ventilation, plus 5 Ach from mechanical means i.e. these values
are by definition the minimum legal requirement. Whilst these are
performance based alternatives to the prescriptive criteria they are
considered worthy of credit. It should be noted that specifying higher
values may result in negatively pressurizing the building and causing
other IAQ problems with in flow of air from other spaces.
Elsewhere, ASHRAE 62.2 [2] states that kitchen fans are mandatory as
this standard considers that windows do not provide sufficient ventilation,
although this standard specifically applies to low rise residential units (3
storeys or less above grade) and wind conditions may not be as
favourable for ventilation as in the case of high rise buildings. The basic
requirement is that a vented cooker hood can exhaust 100 cfm (approx
50 l/s). An alternative approach is that ventilation (either continuous or
intermittent) of 5 Ach be achieved.
1 Buildings Department. Practice Note for Authorized Persons, Registered Structural Engineers and Registered
Geotechnical Engineers, PNAP No. APP-130 Lighting and Ventilation Requirements - Performance Based Approach.
2 ASHRAE 62.2-2003. Ventilation and Acceptable Indoor Air Quality in Low Rise Residential Buildings. American Society of
Heating, Refrigerating and Air Conditioning Engineers. Atlanta. 2003.