Environmental Engineering Reference
In-Depth Information
of people who are involved - particularly at low noise levels - and currently the ben-
efits of modern and rapid transport outweigh the hazards. But concern for vulnera-
ble groups in the community is an important future issue.
A recent report (Porter et al, 1998) explored the possibility of using existing know-
ledge on the potential health effects of environmental noise to define future noise
targets and standards for the UK government. However, despite clear indications of
a number of potential effects of noise on health in the literature, mainly regarding
annoyance and sleep disturbance, the report concluded that, because of the confused
state of knowledge of non-auditory health effects, it was not currently possible to use
them as the base for noise standards. It seems that we have not moved far from the
conclusions reached by an exhaustive review by Miller in 1974, in which the only
conclusively established effect of noise on health was that of noise-induced hearing
loss, though it was accepted that noise can disturb sleep, be a source of annoyance, inter-
fere with communication and performance at complicated tasks, adversely influence
mood and disturb relaxation. In short, the author concludes with the lines 'noise can
affect the essential nature of human life - its quality' (Miller, 1974).
O
UTDOOR
AIR
QUALITY
Many residents who live close to airports often regard the negative effect of pollu-
tion from aircraft and traffic exhaust as a concern. In a similar manner to noise, odours
associated with aircraft movements and evaporative emissions can also increase anxi-
eties regarding air quality amongst the general population. These air pollution issues
often come to a head at the planning stages of airport expansion, and are typically
one of the key issues within the airport's environmental impact statement (Abdel
Aziz et al, 2000).
The primary locally problematic gaseous emissions from aircraft are nitrogen
oxides (NO
x
), carbon monoxide (CO) and non-methane volatile organic compounds
(NMVOCs). NMVOC is a collective term for organic atmospheric compounds and
includes materials found at airports such as benzene, polyaromatic hydrocarbons, ker-
osene, diesel fuel and de-icing compounds, such as ethylene glycol. NMVOCs will
be the major contributor to the odour problems often associated with airports. Other
air pollutants associated with the airport support traffic infrastructure are sulphur
dioxide (SO
2
), ozone (O
3
) and particulates (PM
10
). Overall air pollutant emissions
tend to make a small contribution to the pollutants in a region. However, as this is
highly localized, it can be significant with respect to the immediate vicinity of the air-
port, and it is likely, certainly in the vicinity of major international airports, that local
air quality standards are exceeded.
The air pollution associated with airports has two major sources: first, the pollu-
tion generated by air transport movements and, second, the emissions from the
transport infrastructure, which services the airport - road and rail, etc.
The main sources of air pollutants at airports are listed below.
Aircraft operations
Aircraft operations include movements in the landing and take-off (LTO) cycle -
approach, climb out, taxi, take-off, landing and holding will have different emissions
