BS EN 1793-2-2012 pdf download.Road traffic noise reducing devices Test method for determining the acoustic performance Part 2: Intrinsic characteristics of airborne sound insulation under diffuse sound field conditions.
This BS EN 1793-2 specifies the laboratory method for measuring the airborne sound insulation performance of road traffic noise reducing devices in reverberant conditions. It covers the assessment of the intrinsic performance of barriers that can reasonably be assembled inside the testing facility described in EN ISO 10140-2 and EN ISO 10140-4.
This method is not intended for the determination of the intrinsic characteristics of airborne sound insulation of noise reducing devices to be installed on roads in non-reverberant conditions.
2 Normative references
The foowing documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references. the latest edition of the referenced document (including any amendments) applies.
EN 1793-3, Road traffic noise reducing devices — Test method for determining the acoustic performance — Part 3: Normalized traffic noise spectrum
EN ISO 10140-1, Acoustics — Laboratory measurement of sound insulation of building elements — Part 1:
Application rules for specific products (ISO 10140-1)
EN ISO 10140-2, Acoustics — Laboratory measurement of sound Insulation of building elements — Part 2:
Measurement of airborne sound insulation (ISO 10140-2)
EN ISO 10140-4, Acoustics — Laboratory measurement of sound insulation of building elements — Part 4:
Measurement procedures and requirements (ISO 10140-4)
3 Symbols
For the purposes of this document, the following symbols apply.
4 Test arrangement
The test arrangement shall be as described in EN ISO 10140-1, EN ISO 10140-2 arid EN ISO 10140-4 for partitions with the following modifications:
— The test specimen shall be mounted in the test opening and assembled in the same manner as the manufactured device is used in practice with the same connections and seals between component parts. The edge supports shall not overlap the sample by more than 70 mm and shall be sealed to prevent the leakage of sound.
— Where posts are employed in construction, at least one post shall be included in the specimen with panels attached on both sides. The length of the panels on one side of the post shall be  2 m (see Figure 1). The side that would face the traffic shall face the source room.
— The sample under test, excluding the plirith for levelling, shall have a windowed area not less than 9,5 m2.
— The sample surface area to be used in calculations shall be the total surface area of the sample excluding the plinth for levelling and the overlap surface of the edge supports.
where
DLR is the single-number rating of airborne sound insulation performance expressed as a difference of
A-weighted sound pressure levels, in decibels;
R1 is the sound reduction index in the P’ one-third octave band;
is the normalised A-weighted sound pressure level, in decibels, of traffic noise in the P’ one-third octave band defined In EN 1793-3.
NOTE AnneA B pi’ovides gudance on the use of the single-number rating.
6 Measurement uncertainty
The uncertainty of results obtained from measurements according to this European Standard shall be evaluated, preferably in compliance with ISO/IEC Guide 98-3. If reported. the expanded uncertainty together with the corresponding coverage factor for a stated coverage probability of 95 % as defined in ISOIEC Guide 98-3 shall be given. More information on measurement uncertainty is given in Annex C.
7 Test report
7.1 Expression of results
The one-third octave band values of the sound reduction indices Rj shall be given at all frequencies of measurement in tabular form and in the form of a graph. The indices shall be rounded to the nearest first decimal place.
The single-number rating of airborne sound insulation DLR shall be reported after being rounded to the nearest integer.
If the airborne sound insulation performance is to be categonsed then this shall be in accordance with Annex A.
7.2 Further information
The test report shall include the information listed below:BS EN 1793-2-2012 pdf download.