1. NOISE MAP AND OTHER STUDIES IN A SMALL SPANISH CITY
Valentín Gómez Escobar, Juan M. Barrigón, Alfredo Bravo, Juan A. Méndez Universidad de Extremadura, Dpto. de Física
E. Politécnica Cáceres, Spain
(Garmisch-Partenkirchen; 6-July-2000)

2. Exposition: 1.- Introduction 2.- Methodology 3.- Results
ICSV 7
Exposition:
1.- Introduction
2.- Methodology
3.- Results
Determination of the daily evolution of the equivalent noise level (Leq).
Noise map.
Study of railway noise.
4.- Conclusions

3. Introduction
1.- Introduction

4. Inhabitants: 16000 Surface 1,7 km2
Introduction
Inhabitants: Surface 1,7 km2
Navalmoral de la Mata

5. In this communication we present:
Introduction
In this communication we present:
Noise maps:
Working days in daytime.
Regular squares in whose nodes, measurements were taken.
Hour intervals of measurements were determined by means of weekly measurements of equivalent noise level (Leq).
Vacation (August 1999) and non-vacation period (September-October 1999) were analysed.
We have also taken specific measurements near the railway line in order to study its influence in noise levels.

6. Methodology
2.- Methodology
A) Daily evolution of the equivalent noise level (Leq):
Purpose: divide the day in different independent time intervals.
Weekly measurement in balconies.
Firstly, Type II sonometer (15 min measurements) was used  dynamic margin was selected.
Secondly, Type I sonometer (B & K, Model 2236) (1 min measurement) was used  division of the day in almost uniform Leq time intervals.

7. B) Noise maps of the city (vacation and non-vacation period)
Methodology
B) Noise maps of the city (vacation and non-vacation period)
Division of the city in 200 m squares.
Measurements in square corners or nearest access (59 points)
15 min; four measurement by point; time intervals: 8:00-12:00; 12:00-14:00; 14:00-16:00 and 16:00-22:00.
Working days; appropriate meteorological conditions.
ISO 1996 normative; B & K 2236 (tripod; anti-wind screen)
Calibration: B & K 4231 calibrator.
C) Study of the railway noise.
Two points of sample (12 m from the railway line)
First point: noise dominated only by railway
Second one: railway and traffic noises superposed.
Measurements of 1 second during 20 min. Sampling period began 10 minutes before the train passing.

8. 3.- Results A) Daily evolution of the equivalent noise level (Leq):
Monday
Sunday
Graphic representation of the equivalent level as a function of the time.

9. A) Daily evolution of the equivalent noise level (Leq):
Results
A) Daily evolution of the equivalent noise level (Leq):
The maximum Leq : 74. dBA (on Monday at 1:42 p.m.)
The minimum Leq: 37.3 dBA (on Friday at 6:12 a.m.)
Night interval: from 3:00-4:00 a.m. to 7:00 a.m.
Equivalent average values and their standard deviations, for the selected hours intervals.

10. B) Noise maps of the city
Results
B) Noise maps of the city

11. B) Noise maps of the city
Results
B) Noise maps of the city
Leq noise map for August.

12. B) Noise maps of the city
Results
B) Noise maps of the city
Leq noise map for September.

13. B) Noise maps of the city
Results
B) Noise maps of the city
Similar noise map for non-vacation period (8 instead of 5 points over 60).
Histograms of Leq for both periods:
More dispersion in vacation measurements.
Only 6% and 8,5% measurements over 65 dBA (reference for a acceptable good development of daily activities-OECD).

14. C) Railway noise Results Leq (30 s)= 84.6 dBA. Lmax = 95.7 dBA.
Leq (20 min) = 68.5 dBA. Leq (without train) = 45.0 dBA.

15. C) Railway noise Results Leq (30 s)= 89.3 dBA. Lmax = 94.1 dBA.
Leq (20 min) = 74.3 dBA. Leq (without train) = 68.2 dBA.

16. 4.- Conclusions Conclusions
a) Non-vacation period shows higher results although differences with the vacation one are not too important.
b) The size of square must significantly influence in the value of the equivalent level associated to a certain area in a town.
c) A higher uniformity in the environmental noise during the non-vacation period can be deduced.
d) The impact of the railway noise for a little town can become very significant in relation to the remainder noise sources.