Technical information, February 2007 Makrolon Sound protection

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Product liability clause: This information and our technical advise - wether verbal, in writing or by way of trials - are given in good faith but without warranty, and this also applies where proprietary rights of third parties are involved. Our advice does not release you from the obligation to verify the information currently provided - especially that contained in our safety data and technical information sheets - and to test products as to their suitability for the intended processes and uses. The application, use and processing of our products and the products manufactured by you on the basis of our technical advice are beyond our control and, therfore, entirely your own responsibility. Our products are sold in accordance with the current

Sound protection The human ear perceives an increase by 10 dB(A) as a

doubling of the loudness, i.e. car traffic noise (70 dB) is twice as loud as business office noise (60 dB).

Excess noise and continuous, disturbing noise are harmful. That is why the effect of noise needs to be kept down to a minimum. Particularly relevant in this context are sound protection in residential buildings and the shielding of road noise (noise barrier walls). Depending on the type of noise source, its location with respect to the area to be protected and the path via which the sound is transmitted, various sound protection measures are needed. Basically, a distinction is made between measures aimed at sound absorption via sound dissipation meaning that the acoustic energy is converted into other forms of energy (usually heat) and those used for sound reduction via reflection of the sound waves. Makrolon mono and multi sheets belong to the second category.

Sound reduction A distinction is made between the mean sound reduction index, Rm, and the weighted sound reduction index, Rw. Rm Rm is determined according to DIN 52210, Part 1, i.e. the sound reduction is measured with respect to the frequency and then the arithmetic mean value is calculated. Rw The sound pressure levels and the sound reduction

indexes are expressed in decibel (abbreviated as dB). For the practical assessment of the sound reduction, however, the weighted sound reduction index, Rw, which takes account of the subjective effect for the various frequencies, is used.

The sound pressure level associated with the subjective loudness of common noise sources is given in Table 1. Subjective loudness Sound pressure level in

dB (A) Noise source

Painful 140 Jet aircraft takeoff in immediate vicinity Intolerable 120 Pneumatic hammer at 1 m 110 Night club Extremely noisy 100 Motorcycle Very noisy 90 Machine shop Moderately noisy 80 City motorway 70 Car traffic noise at approx. 50 km/h Quiet 60 Business office 50 Normal conversation Very quiet 30 Whispering 20 Ticking of a clock 0 Threshold of hearing Table 1

version of our General Conditions of Sale and Delivery. Makrolon is a registered trademark of Bayer AG MF 1008 e

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Technical Information, February 2007 Makrolon Sound protection Sound reduction indexes Makrolon multi-wall sheets have the advantage of being

a compact system. Single-sheet glazing

Makrolon multi UV Rm/dB Rw/dB 2/6 - 17 2/8 - 19 2/10 - 20 3/16 - 21 4/10 - 17

5X/32 - 18

Thickness in mm Makrolon GP

Rm/dB Rw/dB 4 23 26 8 27 30

10 29 32 12 - 33 15 - 33

By comparison, a 6-mm thick silicate glass sheet has the following reduction value:

Noise barriers

Rm = 29 dB; Rw = 31 dB Germany A 10-mm thick Makrolon sheet with an area weight of 12 kg/m2 therefore has the same sound reduction effect as a 15-kg/m2 silicate glass sheet.

In accordance with ZTV LSW 88, road noise barrier walls are required to reduce traffic noise by at least 25 dB. Transparent Makrolon UV or Makrolon AR (hard coated) exceed the standard already from 8 mm thickness.

Multi-sheet glazing Multi-sheet glazing is possible by combining 2 or more Makrolon GP sheets or by using Makrolon multi-wall sheets.

They must also display other characteristics, e.g. fire resistance etc., which are guaranteed by Makrolon. Makrolon solid sheets from 8 mm thickness comply with the 25 dB minimum sound reduction index imposed by ZTV LSW 88.

A significant sound reduction can be obtained by combining solid sheets.

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Bayer Sheet Europe GmbH Otto-Hesse-Strasse 19/T9, 64293 Darmstadt, Germany Tel. +49 6151 1303 0 Fax +49 6151 1303 500

Makrolon

GP in mm

Air space in mm

Makrolon

GP in mm

Rm/dB Rw/dB

4 50 4 31 31 4 150 4 38 39 6 30 6 31 32

10 30 10 38 40 10 60 10 43 45

For noise barrier walls on sections of the German motorway, the sound reduction values must be demonstrated in relation to the frequency. Makrolon GP sheets 8 mm thickness can be used for this purpose.

www.bayersheeteurope.com sales@bayersheeteurope.com

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Technical information, February 2007 Makrolon Sound protection France In France, the requirements of standard NF S31-089 apply. Makrolon GP conforms to this standard. Makrolon GP Sound reduction according to NF S31-089

in mm Measured in dB

Minimum requirement in dB

8 29 29 10 31 30

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Product liability clause: This information and our technical advise - wether verbal, in writing or by way of trials - are given in good faith but without warranty, and this also applies where proprietary rights of third parties are involved. Our advice does not release you from the obligation to verify the information currently provided - especially that contained in our safety data and technical information sheets - and to test products as to their suitability for the intended processes and uses. The application, use and processing of our products and the products manufactured by you on the basis of our technical advice are beyond our control and, therfore, entirely your own responsibility. Our products are sold in accordance with the current version of our General Conditions of Sale and Delivery. Makrolon is a registered trademark of Bayer AG MF 1008 e

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