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BEAM P
LUS FOR
E
XISTING
B
UILDINGS
I
NDOOR
E
NVIRONMENTAL
Q
UALITY
(I
EQ
)
V
ERSION
1.2
I
EQ
7 O
UTDOOR
S
OURCES OF
A
IR
P
OLLUTION
Copyright © 2012 BEAM Society Limited. All rights reserved.
Page 120
conditions, particularly wind speed and direction, it is expected that due
account is taken and that measurements will be taken under typical or
average climatic conditions.
Where access to premises is limited, e.g. due to the presence of tenants,
the onus shall be on the Client to demonstrate measurements in those
areas that are accessible is representative of the building as a whole.
Where it can be demonstrated that the identified pollutants are unlikely to
exceed the limits prescribed, and as determined from an appropriate
sample of measurements the relevant credit(s) shall be awarded.
Where certification under the IAQ Certification scheme is current and
covers all parts of the building for which this BEAM version certification is
being sought then the credits shall be awarded.
B
ACKGROUND
This section deals with pollutants found in indoor air which are mainly
attributable to sources external to occupied spaces when the sources
attributable to occupants and their activities is excluded. In the case of
occupied/habitable rooms in air-conditioned/naturally ventilated buildings
the concern is indoor air pollutant from outdoor sources whilst operating
in the naturally ventilated mode. Undertaking appropriate measurements
in air-conditioned buildings will demonstrate that the design and
construction of the building and services serve to reduce indoor air
pollution from all sources.
CO is a toxic gas which interferes with the oxygen transport capacity of
the blood, and at levels to which people can be exposed in buildings,
leads to symptoms such as headaches, nausea, chest constriction, etc,
as well as affecting concentration. Exposure to oxides of nitrogen (NO
x
,
NO
2
) can result in irritations to the eyes and respiratory system. Sources
in occupied areas include infiltration from vehicle exhausts and enclosed
car parks, and incomplete combustion within premises. O
3
irritates the
eyes and respiratory system. Sources of O
3
in occupied areas include
infiltration from outside occupied areas, and from equipment which
utilizes ultra-violet light or causes ionization of air.
Respirable Suspended Particles (PM
10
) are suspended airborne particles
with a nominal aerodynamic diameter of 10 µm or less. The health
impacts from inhalation of particles depend on size, shape and chemical
reactivity. Outdoor sources are numerous, but vehicular exhaust and
construction activity contribute significantly. Particulates from outside
sources are carried into air-conditioned buildings through outside air
intakes and through uncontrolled infiltration. Indoor sources include air
ducts, equipment and user activities. Levels of RSP may be used as an
indicator of the effectiveness of the air filtration system, so sampling
should be carried out at one representative zone in each type of
premises.