Norway. The traffic at. Oslo. Airport. Fornebu that includes both national and ... 1800 new respondents were subjected to identical interviews in the same. 15.
N9 O- 24 87_)__ 7/ c__./-
AN
AIRCRAFT
NOISE
Truls ......... ELAB-RUNIT
The
IN
NORWAY
Gjestland and
K_re H Norwegian
N-7034
• Civil
T
STUDY
Liasjo Institute
Trondheim,
of
Technology
Norway
Hans Einar Bohn Aviation Administration Oslo,
Norway
289
PRECEDING
PAGE BLANK
NOT
FILMED
Introduction
An
extensive
study
of
conducted in that includes
Oslo, both
Norway. national
approximately
350
scheduled the bulk The
political
been
with aircraft they are also
During
the
serves traffic,
most was
The
summer
part
Outline
A
noise
both
The the
aircraft
In
the
same
areas. flight both be
accurately
In
Norway
EFN. This calculated
study
290
Fornebu totals
are
size
regular
aircraft,
airport
unti!
Osio
to
the
replace
late
nineties
continue,
Airport
and
therefore summer
Gardemoen,
transferred
of
which can
1989
was
to
which
Fornebu. to
traffic operation.
possibility Fornebu.
some
.... the
expected
the re_11ar be put into
unique around
the_ to
to
will The study
road
was
designed,
traffic
noise,
including A
random
study areas were contacted represent different noise
relative
to
the
in
aircraft
the noise
and
flight
a 2 from noise
airport monitoring
period
the
on
is
sample
of
for an levels and
paths.
week period just prior Gardemoen to Fornebu. was
equipped_a system.
an
questions
average
monitored The
in
all
to
15
permanent noise situation
basis
can
therefore
described. the
official
index LDN
aircraft
is quite at Fornebu.
traffic pattern less than ! dBA, partly effective operations
was
were conducted charter traffic
period
the
new
1989,
the
in 15 areas
In addition track and in
these
large
in Oslo will to increase.
survey
and
of
a
represented a the communities
locations
interviews transfer
and
of
being Airport flights,
....
but
level to new airport
social
1650 respondents interview. These different
250
Oslo
study
comprehensive
on
Of
during
therefore impact on
of
build
traffic
the maximum before the
situation the noise
currently
charter traffic and intercontinental refurbished. From May till September
the
traffic
is
day:
made,
noise expected
months
of the being of
total
resemble increase
to
already
problems degree
per
intermediate Boeing 737
decision
has
noise
The traffic at and international
movements
flights with being DC9 and
Fornebu
major
aircraft
between
noise
similar For
to this
exposure
index
CNEL. However, we particular aircraft
is
called
have also mix and
the difference between EFN and LDN was slightly with EFN being the larger quantity. There is night curfew at Fornebu with no scheduled Ii
pm
and
7
am.
a
In August identical
a group of interviews
measurement
program
1800 new respondents in the same 15 areas, was
were and
subjected the noise
to
repeated.
Results
Only
the
far.
In
results this
question The
on
respondent
very
Norwegian,
The
results
percentage aircraft function
Modeis
are
noise
of
Schultz's
the
In
previously
Fidell
et
al.
was
purely
a
experiments noise
(2)
a
good
have
level
not
the
that
threshold different
elaboration following
on
of
based
was
on
and
threshold
the
we
a
is a
introduction certain has been
concluded noise
that above
a
annoyance. between
dose-
different simple
criterion see Figure concept
it
above a concept for
in very
by
as
and
known
lacking
noise
differences appeared using a
well
annoyed"
noise This
for
annoyance
his
calculated
and varying communities, the
mathematical
and
it
(4),
descriptor
shown
a
degree
empirical,
model
a
the
shows
presented
assuming that only to the annoyance.
based on associated further
or
written
translated).
give
(2),
relationships that have can be accounted for by
suggest
YES, we this noise
annoying
"highly 2.
publication
response surveys
A
so
direct
when
naturally
diagram
to
percentage see Figure
presented
is
fixed with
The
made
Schultz
laboratory
threshold
been
the
energy-equivalent
given
i.
(I)
in a later foundation.
by
a
of people asked: Can you hear the noise very annoying as a noise level in each location.
1978
threshold (3), could contribute
validated
noise
been
between
relationship
have
aircraft
was
relationship
describing polynominal,
pointed out theoretical
to
little
have
Figure
have
the
exposure.
synthesis, third order
analyzed
annoyance
attempts of
a
examples in
been
responses
answer was you consider
questionnaire
these
given
hear
if the "Would
(of the total number noise .... ) considering of the outdoor aircraft
number
of a level
you
annoying,
original
have
the noise.
"Can
moderately (The
description
We
aircraft
asked:
and
for
noise
survey
present
your home ?", and follow-up question:
?"
in
spring
will
to
was
annoying,
annoying
the we
reaction
being outside presented a
A
from
report
noise model
value 3. has
led
us
to
hypothesis: 291
100-
G 70.±_-
>0 z
z Lad
_
>-
L_
Z Z
60-
,c_
!---
•==:: z
@
50,
@
40-
@
30-
@
20-
@@
@ @
i
10
o
1 1_.J
40
Figure
292
i
'
I
4.5
I.
,
i_._
i
i
50
= i
i
J I
55
= i
i
,
I
80
i
J i
i
I
65
_
I
i
i
I
i
s Q
70
Results from the Fornebu survey Percentage of people very annoyed as a function noise exposure. Circled numbers indicate number respondents for each noise level.
i
75
dB (EFN)
of of
2
100 % HA = 0.8553
Ldn
-
0.0q01
Ld
+ 0.00047
3 L"nu
gO
80 7O
¢:
< S0 O_ mm
X
,,.,
q0
el) Iu
,,_
3O 2O
10
q0
50
60
70
80
90
l_n (decibels]
Figure
•
Dose-effect relationship with general transportation Schultz; 1978
for
annoyance associated noise according to
293
8O
Criterion
= 1.05
----
Criterion Criterion Criterion
= 2.1 = tl.2 = 8.LI
.....
Criterion
= 16.8
7O
0 rr-
/
GO
< t-
/
/
SO
/ S
/
Q 01
_0
/
U I.,
3O
2.
2O
10
Figure
3.
Effect annoyance
294
of
changing on
criterion
dose-effect
for relationship;
reporting
high Fidell
et
al.
1987
There
are
two
individual's threshold, certain
basically
response the noise
"disturbance".
region follows Fechner's laws relationship level In
dB
which the annoying".
We
suggested
there
the
people And
or
it
has
In
of
terms
individual noise
reaction has
levels
certain broken,
a
silently agreed the reaction is mode'. different
The
to
this
this
transition
this but
level is expectations,
an
the
individual activity,
rather
reasons discussion.
we
than may
a still
use
as
the
a
'contract' above the
is limit
immediately, and the 'disturbance follows
Weber's
a
and
versus line.
Fechner's
noise
between
can at a
plot
degree
of
be depicted by certain threshold
and time
will have therefore noise a
the
an
long
follows
quantity location,
fixed
when
that
as
threshold
people within a community a community basis we will
and
the between
appear
relationship
noise exposure discontinuity
infringed
lawyers
reaction
again
the
being
and
Hence a reaction also be a straight
a
interval
for simplicity level for our
the
live
their content). obviously, until
implies
tolerance,
above
hypothesis
he
order to are not
certainly
which
'contract'
of
'model',
with
etc. Different thresholds. On
the limit,
noise
and
in
with
'annoyance', breached."
the individual different kind to
and
nature of boundaries
reacts than in
disturbance/annoyance two straight lines level.
The threshold depending on
the the
upon, of a
reaction
to
matter
When the increases
psycophysical
at
to "really threshold
is
as explained above. that is, the noise
laws should be applicable. in this level region will According
and
'agreement'
realized determine
and be
noise
however,
ourselves 'contracts'
stickier
limit
below
a
known (much less not enforceable,
noise
certain
stay
pattern however;
to
and the
and
T.J.Schultz
recognized,
a
quite that
this
Weber's showing
level,
with
their
becomes
in
explanation: among These
even
an
a certain only a
stimulus
theory, function
certain
hypothesis
that
_'disturbance' been felt
a
a
"just disturbing" be explained by
is never They are
realize
then
a
possible
courts who have never 'implicit contracts' undeniable contract
to
to
line.
'contracts' communities.
acknowledged
govern
disturbance/annoyance
is
from may
following adopt in
of
that
low levels up and represents
response
straight
changes situation
number of 'clauses' But they are there. enough
a
discussed
the
" I think we close together
the
degree be
situation
noise This
concept.
processes
traditional psycophysical may be applied. Hence
should
given
usually
If
between
in
any
upon.
different to noise. At is "tolerated"
single
may of
vary day,
different see a
threshold,
but
threshold
295
Reported differences in community reaction to noise may thus be explained by differences in the threshold level for onset of the annoyance reaction. In a busy community with a high ambient noise level, we may expect a high tolerance threshold, where as the people living in a quiet rural area have a low threshold. This fact makes it impossible to compare dose-response relationships found in one community with those from another community without considering the possibility that the 'community reaction thresholds' are different. The threshold is most likely associated with the instantaneous noise level rather than the equivalent level or a similar 'average _' noise index. Differences in the reported annoyance areas with equal LEQ may therefore also be explained by differences in the noise exposure pattern, even though the reaction thresholds are the same.
in
At a conference in 1988 we presented a paper indicating that location relative to the flight path was an important parameter for predicting the annoyance from aircraft noise (5). People living underneath the take-off flight path seemed to report a higher degree of annoyance than people living outside those areas. For equal LEQ each noise event observed underneath the flight path has a shorter duration and higher maximum level than at other locations. This means that people living underneath the flight paths are more likely to feel that 'their contract has been breached', and they react more often according to the 'above threshold psychophysical model'.
Discussion In figure 4 we have fitted linear regression lines to the results from the Fornebu study. The dashed line (r=.865) is fitted to the complete data set. We get a better fit, however, if we assume a change in the reaction pattern around 60-65 dBA. The two solid lines are based on data points 42-65 dBA (r=.911) and 60-74 dBA (r=.878). These results indicate a possible discontinuity in the 60-65 dBA region. According to our previous findings we respondentsinto three groups depending using the information from the flight define flight areas
296
divided the different on their residence. By track recorder we could
three types of locations: areas underneath paths, areas underneath the take-off flight never (or seldom) overflown.
the approach paths, and
: R-0.865 1 : R-0.911 2 : R,-0.878
90-
8O
G 7O LLI 0 1,1 z >CD Z Z
zZ >.-
c=:
60.
®
50.
LLI
I'--Z LLI
40'
,,,
30'
C__
2010-
40
50
55
60
65
70
75
dB (EFN)
t" f J
Figure
4.
Results from the Fornebu survey Percentage of people very annoyed
as
exposure. Dashed line: linear regression to Solid line: two regression lines,
all data points 42-65 dBA and 60-74
a
function
of
noise
dBA
297
Figure 5 shows path areas. A
the response from single regression
coefficient r=.701 for the 42-65 dBA 60-74
dBA
Figure
6
total
where region
region shows of
Figure 7 A single the same
results
from
respondents
is
noise exposure fitted to the is r=.789.
shows the results regression line exposure regions
coefficients r=.953 (365 respondents).
two-stage respondents)
method and
approach
yields r=.484
r=.775 for the
respondents).
similar
number
experiencing is therefore coefficient
(149
as a (477
people living in the line has a correlation
the
only
above whole
take-off
242
60 data
areas.
with
dBA. set.
A
most
The
of
them
regression line The correlation
from areas outside the flight gives r=.908, whereas two lines as above have correlation
(730
respondents)
and
paths. for
r=.747
Conclusions
The total conclusions. have these We
material is not large In the next phase
the results from an results will confirm
think
the
areas can are exposed
higher
probability
of
rather
the
than
according
'disturbance
One way of discriminating contributes to annoyance great enough magnitude introduce
a
equivalent level noise
threshold level
exceeds annoyance.
equivalent regular annoyance
level LEQ
in (4).
Moreover, this In his book, different
a
he points out: and the standard LTEQ (annoyance presents than the
298
observed that noise
measured
We
only
for
model'
greater.
shown
in
those
LTEQ,
subjectively
LTEQ, is based Noise Ratinq,
indices.
take-off these areas and hence the
"annoyance
becomes
have
threshold,
predicting
Hopefully
the in
In
a
(3)
periods
is
that
superior
comparison
plausible-looking
the
to
the
noise
between
to
noise
for that
psychophysical Schultz reviews
fit
of
the
descriptor confirmed
reported
on a (6)
that
LEQ
"Not only is the correlation coefficient error of estimate lower for the plot versus noise exposure), but the latter
a much more LEQ curve."
will
noise exposure that actually from noise exposure that is not to be recognized as such is to level.
with
in
people levels,
to-the
model'
we
respondents.
certain threshold is a good Laboratory experimentshave
index, Community
noise
score
by the fact instantaneous
reacting
to draw firm study, however,
additional 1800 our hypothesis.
annoyance
be explained to higher
enough of the
the
data
model.
and
LTEQ
higher against curve points
the
100-
90
80
70 UJ >O Z Z
®
60
@
50 _Z 0
•
W cz_ U_
30
2O
I0
o
I _l._
40
Figure
5.
I
i
l
45
z
_I_
i
]
50
i
l
I
i
I
55
i
i
i
I
I
60
i
z
i
i
I
65
I
i_*|
l
i
70
i
i
l
l
I
75
dB (EF'N)
Results from the Fornebu survey Percentage of people very annoyed as a function of noise exposure for respondents living under the approach flight paths. Dashed line: linear regression to all data points Solid line: two regression lines, 42-65 dBA and 60-74 dBA
299
100 -
9O
80-
LLI >-0 Z ILl (...) Z
•:z:
>C_ Z Z
®
70-
/
60-
/ /
>..
,._
ILl _.
/
50. /
I---
,,=z: z
4.0.
LLJ /
L._ eL.
/
®
30'
20.
/ / =
/ 10
o I
I
40
Figure
300
6.
I
]
|
I
45
i
I
I
I
I
50
I
I
I
I
I
55
i
i
|
I
i
I
I
_
60
Results from the Fornebu survey Percentage of people very annoyed as exposure for respondents living under path. Linear regression to all data points
I
I
65
a
i
i
i
I
I
I
I
70
function of the take-off
I
i
75
dB (EF'N)
noise flight
1009O
®
8O
70.
t.u
60,
•=:z:
50,
>0 Z Z
Z Z
I--Z
"'
30-
LIJ
_-
®
20
®
10.
O'
I
4.0
Figure
7.
I
I
l
i
_._p,
_--_u
4_.._
i
t.j'
so
i
i
I
i
_5
u
u
i
I
i
eo
,
n
i" I
I
65
i
i
u
I
i
:,o
o '_
I
75
da (EFN)
Results from the Fornebu survey Percentage of people very annoyed as a function of noise exposure for respondents living outside the flight paths. Dashed line: linear regression to all data points Solid line: two regression lines, 42-65 dBA and 60-74 dBA
301
With the Airport, is
a
combined we hope
function
data from to confirm
of
and that this rather than a
exposure
to
noise
experienced
these
areas
may
surveys noise in
be
that
above
rural
around Fornebu that the annoyance a
certain
threshold,
on community expectations If this conclusion is valid,
around in other
busy airports areas, for
areas.
expected
the
two surveys hypothesis
noise
threshold depends fixed quantity.
results from noise to predict aircraft
probability
the the
to
The
be
annoyance
cannot instance
be en
reaction
to
noise
higher,
as
the
much
threshold
is
exceeded,
used route
in is
higher.
References (I)
Schultz,
T.J.:
Synthesis
of
Annoyance, (2)
Fidell,
S.,
Green, A
D.M.,
Social
Surveys
on
J.Acoust.
Soc.Am.
vol
Schultz,
Strategy
for
T.J.,
BBN Report Inc, Canoga
(3)
Gjestland,
T.,
Oftedal, J. Sound
G.: Vib.
(4)
Gjestland,
T.:
Assessment Traffic
of Noise,
(5)
Gjestland,
T.:
New Support Assessing
for a Annoyance
Proc.
ICBEN
5th
Health (6)
Schultz,
T.J.:
Applied
Noise Science
302
a
good
friend,
Annoyance
from Road vol 112, 1987
Noise
Stockholm,
Publishers,
Ted
Schultz.
as
Sweden,
Rating
Acknowledgment
To
Noise
Threshold Based from Aircraft
Congress
Induced
1987 CA
Noise Annoyance J. Sound Vib.
Problem,
Community
of 1980
1978. K.S.:
Noise
6337, Park,
Assessment vol 69,
64,
Pearsons,
Understanding
Annoyance, BBN Labs
Noise
1982
Method Noise, a
Public 1988
for
