Sigmund Olafsen, siv. ing.
Brekke & Strand akustikk AS
Postadresse: Postboks 1024 Hoff, 0218 OSLO
Besøksadresse: Hovfaret 17B
Sentralbord: +47 24 12 64 40 | Mobil: +47 91
58 38 18
e-post: so@bs-akustikk.no | www.bs-akustikk.no
Norwegian regulations regarding indoor
sound pressure levels have been in force since 1997. In existing residences
exposed to existing noise sources the regulations state that indoor levels shall
not exceed an LAeq,24h of 42 dB. The responsibility of sound reduction
measures lies with the owner of the noise source. The regulation states that
the indoor level is derived assuming closed windows and closed ventilation
devices.
A change in the regulation is now being
evaluated. It would be more realistic to assume open ventilation devices.
Earlier studies have indicated that the critical cases are situations where the
ventilation devices face the noise source directly. The presented investigation
has concentrated on the difference in indoor levels for two types of
ventilation devices common in older houses. Calculations are based entirely on
empirical data. The types of noise sources considered are roads, railways,
trams and subways, two situations for each source. Five general types of houses
of typical Norwegian construction are considered.
The paper will present the reported
results from the calculations based on field data and considerations on the
validity of the methods.
The Norwegian Pollution Control
Authority has commissioned the work, and has permitted the results to be
presented at BNAM.