• Project number: F 2571
• Institution: Federal Institute for Occupational Safety and Health (BAuA) / Physikalisch-Technische Bundesanstalt (PTB)
• Status: Ongoing Project
• Planned end: 2027-08-31

Description:

Noise is bad for health – and machines are among the most common sources of noise in the workplace. To tackle the hazard directly at source, machine manufacturers must specify how loud their machines are in accordance with the Machinery Directive. Among other things, the sound power level is stated – a direct measure of the noise problem associated with a machine.

However, the measurement methods specified in standards are often very complicated. They need special rooms or complicated equipment. As a result, the manuals for around 80% of machines don't include complete or any information about noise according to the NOMAD study from 2012.

A comparably simpler method measures the sound power level in accordance with the EN ISO 3744 standard using microphones placed around the machine. However, this method is also not without effort: it requires measurements at many fixed points. The number of measurement points must be increased even further if the sound is not emitted evenly in all directions from the machine.

The aim of the project is to develop a simpler measurement method that is also practical. To do this, a new method will be tested in which a microphone is used to manually scan a virtual surface around the sound source. Special attention will be paid to how closeness to the sound source affects measurement accuracy.

The outcome of the project will be a practical draft standard that will make it easier for machine manufacturers to meet the legal requirements for noise information. Reliable information on the sound power of machines not only helps manufacturers, it also improves the conditions for the ‘Sell and Buy Quiet’ concept: machine manufacturers develop quieter machines and market them with accurate noise information (‘Sell Quiet’), while employers prefer to purchase quiet machines (‘Buy Quiet’), thus protecting their workers and saving money, e.g. for subsequent noise reduction measures.