The BS EN ISO 10140-2: 2010 test involves placing the door construction within a dividing wall between a sound source room and a receiving room. Sound waves are produced in the source room and measurements of the sound pressure levels are made in both rooms at one-third octave intervals in the frequency range 100 to 3150 Hertz (Hz).
Several microphones are used to obtain a good average of the sound pressure level in each room. From these measurements, the Sound Reduction Index (R) is derived.
These values are then calculated in accordance with BS EN ISO 717-1: 1997 to obtain as single figure weighted sound reduction index (Rw).The ASTM method follows the same principle but performance is measured over a slightly different frequency range, 125 to 4000 Hz and the results are expressed as a sound transmission class (STC).
dB Decibel. A comparative figure generally indicating a decrease in sound level between two points (source and receiver). The dB scale is logarithmic so 10dB is 10 times the power ratio, 50dB is 100,000 times the power ratio and 100dB is 10,000 000 000 times the power ratio of 1dB respectively.
R Sound Reduction Index. Expressed in dB and defined as the number of decibels by which sound energy, randomly incident on the test sample, is reduced in passing through it.
STC Sound Transmission Class. A single figure performance indicator very similar to Rw but derived from ASTM-E413-10. Classification for rating sound insulation. The Rw or STC rating indicates acoustic performance of a door/seal assembly over a wide spectrum of sound frequencies.
Documented test evidence is required to verify the acoustic performance of a door assembly. When looking at any acoustic test report for a doorset or sealing system, it is important to remember the relationship and inter-dependency between the door, frame and sealing system. The wall, floor and ceiling construction will also influence performance.
Door manufacturers' test reports should always indicate how the door perimeter was sealed, including the threshold.
Seal manufacturers' test reports should always indicate the kind of door used to evaluate the sealing system and indeed if a real door was used at all. It is advisable to carefully inspect test reports to determine whether a real or full size operational door assembly was actually tested or smaller sections and portions of the door.
All Lorient sealing systems are acoustically tested in their everyday operational mode. Under laboratory test conditions, it is all too easy to achieve deceptively more impressive results by wedging a door leaf in the frame with the seals in an extreme, highly compressed state – even if the operation of such a door in everyday service would be untenable. Lorient results are truly indicative of practical expectations.
These may be incorporated in doors without a major loss of acoustic performance and in many situations can increase the acoustic performance provided that thick enough glass is used. Lorient System-36 PLUS range of glazing gaskets provides optimum acoustic performance for most types of door constructions including FD30/FD30S/FD60 and FD60S. Please refer to Lorient technical department for further information.
A typical architectural door leaf with FD30 fire performance has a mass of only 18-22kg/m2 below the requirement stated in Approved Document E. Therefore, to meet the requirements of Approved Document E it is essential to establish the acoustic performance of the doorset to at least 29dB Rw.
Door construction can help to some extent. Because sound is created by pressure fluctuations, it is the vibration of the door leaf that causes some of the sound to be transmitted. A very dense or moderately flexible door leaf is harder to set into vibration providing a better acoustic barrier. However, even a heavier door, without seals, will not meet the minimum 29dB Rw requirement. This is because although some sound will be transmitted through the door leaf itself, the majority of the sound passes through the gaps around the perimeter of the door leaf. The reference to Approved Document B should also be noted. In many residential situations, the door that must provide acoustic protection will also need to provide fire and smoke protection. For most purposes, a standard FD30 door leaf will provide a good basis for an acoustic door assembly to meet the 29dB Rw minimum requirement of Approved Document E. However, without a sealing system the acoustic performance will only be in the region of 22dB Rw. Fitting a traditional brush-type smoke seal will offer only a minor improvement in acoustic performance, still falling well below the 29dB Rw minimum required by Approved Document E.
Therefore, for any door assembly, a professionally designed and engineered sealing system for acoustic, smoke and fire containment must be incorporated in order to ensure that the door assembly will comply with the requirements.
A 'good' sealing system can only be determined by testing against the referenced standards, using a full size door assembly, and observing at all times the benchmark of 29dB Rw minimum for the whole assembly.
We offer a number of specialist Testing & Technical Services including acoustic testing. Lorient's brand new state-of-the-art acoustic transmission suite was designed and purpose-built to meet the requirements of BS EN ISO 10140 – Laboratory measurement of sound insulation of building elements.
Our acoustic transmission suite is run by a respected and experienced technical consultant, who will oversee the testing process from start to finish; and guide you through the maze of regulations. Working closely together, we'll design and implement a test programme to meet your specific requirements.
Our technicians have many years' experience building test specimens, and we also offer an installation service. Once the testing programme is complete, a number of options are available including a summary report; or a comprehensive report.
Below are a number of different assemblies that can be tested – there may be many others. Just ask!
Please contact our Testing & Technical Services team to find out more on +44 (0)1626 834252.
Welcome to our help section, please find some useful guidance on how to use 'acoustic search' below.
Top tip – you can click on the 'results' button at any time during the selection process to reveal all available results.
Top tip – you can alter your choice at any time by selecting 'change' and reselecting. The Acoustic search will then filter results accordingly.
Important note: Test data is for guidance on acoustic performance only. Please refer to the fire test evidence on the particular door core to ensure the correct intumescent fire seals and fire rated glass are fitted for FD30 and FD60 applications.
Care has been taken to ensure that the information displayed in our 'Acoustic search' is accurate; Lorient does not accept responsibility or liability for errors or information which is found to be misleading.