Typically all manufactured materials and products emit gasses from
VOC?s (Volatile Organic Compounds) for a period of time. These may have
a distinct odour and are, therefore, perceived as dangerous. There are a
great number of VOC?s and different materials emit different mixes and
concentrations of VOC. The distinctive smell of the interior of a new
car, for example, is the result of VOC emissions, and is perceived as
desirable to many people. All too soon the distinctive smell diminishes
and disappears as the VOC?s are released into the atmosphere.
Installation adhesives
Some adhesives used for the installation of some carpets may
contribute to VOC levels and should be used in well ventilated areas
which should continue to be ventilated for some days after installation
has been completed. Modern adhesives, which have been recently
introduced, have significantly lower emission levels.
New carpet smell
The new carpet smell
is the result of VOC emissions, usually from the back coating material
and it too will diminish and disappear in time dependent upon the level
of ventilation in the room.
According to studies by leading research organisations in the US and
Germany, the contribution made by carpet to
indoor air pollution is minimal compared with many other indoor finishes
and materials. Taking paint as being rated as 100, relative emissions
are adhesives 72.5, wall coverings 8.5, plywood 1 and carpet 0.5.
(i.e. a carpet emits
1/200th of the VOC gasses given off by paint). Such a low level of
emissions from carpet does
not constitute a health risk for consumers.
Indoor Air Quality
Many people are concerned about indoor air quality. An analysis of
the air in a new office building in the USA where the workers were
complaining of discomfort and illness found that the enclosed heated and
air conditioned environment re-circulated rather than dispersed emissions
from the indoor wall, ceiling, floor, and furnishings. Ventilation,
introducing fresh air removed any problems.
Research has shown that wool is particularly effective absorbent of
these gases. A study in the US has shown that wool has one of the
highest rates of removal of nitrogen dioxide from the atmosphere.
Because of the 3 dimensional nature of carpet with
the wool fibres in the pile standing vertically from the backing, the
wool fibres present a considerable fibre area for the absorption of
gases. One square metre of carpet containing
1Kg of wool will present a fibre surface for gaseous absorption of 100
square metres.
Many key research papers show that carpet, in fact, contributes
significantly to cleaner indoor air. Three major pollutants of indoor
air quality are formaldehyde which is emitted from a wide range of
building products, oxides of nitrogen and oxides of sulphur both of
which are by-products of combustion processes (e.g., gas cookers and
heaters).
Other studies have shown that large amounts of sulphur dioxide are
also absorbed and held by wool fibres in carpet.
Summary
Carpet, therefore, contributes significantly fewer emissions than do
other building materials, indoor furnishings and finishes. The capacity
for carpet to
absorb airborne pollutants and to hold these makes it a significant
contributor to good indoor air quality.