Noise pollution can affect people’s health and living comfort. That is why there are rules for noise. One example is the Noise Abatement Act; it contains rules for industrial noise. They for example include how much noise companies are allowed to make at an industrial estate.
If a company or institution exceeds the applicable limit, measures must be taken to prevent noise pollution. The possible measures obviously include acoustic insulation.
Regulations for sound-insulating doors
In view of the fact that sound insulation is a highly relative term, there is a comprehensive standard for acoustic insulation according to which doors are tested and certified: the European EN-ISO 10140 standard, formerly known as ISO 140-3:1995.
The door must be tested by an accredited organisation. The Peutz laboratory meets the conditions for these kinds of tests and is recognised in accordance with ISO/IEC 18025. The Peutz laboratory is accredited by the Dutch Accreditation Council (RvA) under number L334. Testing at an accredited institution allows us, as the manufacturer and supplier, to install the doors throughout Europe. The test is performed in accordance with the applicable standard and test method.
During a laboratory test, the sound insulation of the door is measured by placing the structure to be tested in a test opening between two fully separated, neighbouring test rooms. In one of the rooms, the “transmission room”, sound is produced via speakers. The sound level in the “transmission room” and the neighbouring “receiving room” is measured and registered.
Based on laboratory measurements on the building elements, the laboratory test results ultimately yield the acoustic properties at the various frequencies (Hz), expressed in decibels (dB).
For the test it is not mandatory to test the door as a complete structure. It may therefore be that test results only reflect the acoustic insulation values of the panels, if only the panels were installed for the test. However, for a correct representation of the sound insulation, it is important that the complete door structure is tested. This guarantees that the door will also provide good acoustic insulation in its practical application.
What exactly is Rw (C, Ctr)?
The acoustic performance of a door is (usually) expressed in Rw; this is the ‘weighted sound insulation’ expressed in decibels (dB) and calculated in accordance with EN-ISO 717. It means that the acoustic insulation value of the door, or another building element, was measured in a laboratory in the absence of lateral transmission.
However, in practice there are more noise sources than in a laboratory. To take these into account and to correct the Rw insulation value, the indexes C and Ctr are used. The term C represents ambient noise. The term Ctr represents the noise coming from road traffic in the surrounding area.
However, the Rw (C, Ctr) index does not state at which frequencies the door performs well or not as well. If the noise source in your environment mainly produces low tones, it is important for your door to properly insulate these low tones.