ISO 5128 Acoustics - Measurement of Noise Inside Motor Vehicles

The ISO 5128 standard, developed by the International Standards Organization (ISO), describes the conditions for obtaining reproducible and comparable data on noise levels and noise spectra inside all types of road vehicles, with the exception of agricultural tractors and field machinery.

This standard provides a definition of in-vehicle noise for engineering and contractual purposes . It defines the conditions for obtaining repeatable and comparable measurements of noise levels and noise spectra inside any type of motor vehicle intended for road use, including where the driver and passengers are seated in an open cab or a well-defined area. Only agricultural tractors and field machinery covered by the ISO 5131 standard are not included in this standard (ISO 5131 Acoustics - Tractors and machinery for agriculture and forestry - Noise measurement in operator position - Survey method).

Test results can be used, for example, for:

• To decide whether the noise inside the vehicle complies with the noise characteristics.
• For estimating the risk of hearing damage in conjunction with noise exposure data.
• To assess the degree of speech interference.
• To guide a program of more detailed measurements to study noise reduction procedures.

The test methods described in this standard are not intended for the measurement of pressure swings at very low frequencies, nor for the assessment of exposure to noise for comfort and safety, such as fatigue and alertness. The possibilities of the technique today do not yet allow a good correlation between the measured data and comfort and safety.

The test methods described in this standard are engineering methods defined in the ISO 2204 standard. With the pulse sound level meter, measurements can be made on sources emitting pulsed noise. In addition, according to this standard, when a measurement is repeated with other instruments of the same type or at other measurement sites or with other measuring instruments, differences of plus / minus 3 dB degrees may be observed.

Among the numerous test, measurement, analysis and evaluation studies it provides for businesses in various sectors, our organization also provides testing services for the measurement of noise inside motor vehicles, within the scope of ISO 5128 standard, with its trained and expert staff and advanced technological equipment.