BS EN 12758:2011 pdf download – Glass in building — Glazing and airborne sound insulation — Product descriptions and determination of properties
4.3.4 Coated glasses These are glass panes that have been coated and are in accordance with EN 1096-1. NOTE Coated glass may be manufactured from any of the glass types referred to in 4.1, 4.2, 4.3.1, 4.3.2 or 4.3.3.
4.3.5 Insulating glass units (IGU) These are hermetically sealed insulating glass units, containing air or other gas, that are in accordance with EN 1279-1. NOTE An IGU may be manufactured from any of the glass types or combination of the glass types referred to in 4.1, 4.2, 4.3.1, 4.3.2, 4.3.3 or 4.3.4.
5 Test methods
Acoustic performance data shall be obtained under the conditions specified by EN ISO 10140 and EN ISO 717-1. For laminated glasses, owing to temperature dependency, the specimen temperature shall be (21 ± 2)°C. NOTE 1 For best reproducibility it is recommended that the test opening for glass panes, as described in EN ISO 10140, be adopted. Some variation in panel size, etc., to those in EN ISO 10140, may be necessary for the testing of glazed assemblies, i.e. glass blocks, paver units, channel shaped glass, structural sealant glazing and structural assemblies in order to include a valid representation of all their features. Acoustic measurements of the performance of these products shall be made on assemblies or arrays of them, and not on individual elements. Factors which influence testing are size, jointing, etc.
NOTE 2 For large mixed components it may be more appropriate to employ intensity measurement techniques, according to the advice of a specialist. Test reports on the sound insulation of glazing shall be obtained from measurements made under the conditions specified in EN ISO 10140 or, as closely as possible, for some unconventional glass products or assemblies, as acknowledged above. In all cases, constructional details shall be included, with statements, where appropriate, of:
a) type of glass;
b) glass thickness(es);
c) airspace(s)/cavity width(s);
d) gas filling – type and concentration;
e) for laminated glass, glass / plastics glazing sheet materials / interlayer build up – type, thickness(es) and number;
f) for laminated glass, the specimen temperature;
g) description of the particular mounting conditions employed for assemblies of glass blocks, pavers units, channel-shaped glass, structural sealant glazing, and structural assemblies due to the necessary deviation from the prescribed conditions of EN ISO 10140.
5.2 Reference curves
5.2.1 General These shall be determined by measuring two reference Insulating Glass Units (IGU), as defined in 5.2.2 and 5.2.3. Reference curves shall be determined when the test equipment is set up and then checked at least once a year or before each new glazing measurement. In case of doubt concerning the results obtained using the reference IGUs then a specimen of single glass , i.e. 10 mm float glass in accordance with EN 572-1 and -2, shall be measured to check repeatability.
5.2.2 Reference IGU 6(16)6 The Sound Transmission Loss (STL) of a reference 6(16)6 IGU as described in Annex A; Figure A.1 shall be in the range as given in Table 1:
When the absolute deviations between the numbers in Table 1 and the measured values are summed then the total deviation cannot exceed 4,0 dB. All calculations shall be undertaken with an accuracy of 0,1.
5.2.3 Reference IGU 10 (16) 44-2 laminated glass with acoustic interlayer S
The STL of a reference IGU made up of 44-2(16)10 shall be in the range as given in Table 2.
The laminated glass being manufactured with an acoustic interlayer S. The IGU is described in Annex A;Figure A.2
NOTE 1 A laminated glass make up designated 44-2 means 2 x 4 mm glass and a 0,76 mm interlayer.
When the absolute deviations between the numbers in Table 2 and the measured values are summed then the total deviation cannot exceed 4,0 dB. All calculations shall be undertaken with an accuracy of 0,1.
External reproducibility of R w , R w +C and R w +C tr of measurements done following the above rules will be ± 1 dB.
NOTE 2 This data results from a round robin covering 22 laboratories. The values have been obtained by taking the average value ± one standard deviation.
5.2.4 Maximum standard deviation of repeatability
Maximum repeatability shall be in accordance with ISO 140-2 1991, as reproduced in Table 3.