Measuring the noise exposure level at the workplace (EN ISO 9612)

Employee wearing hearing protection in front of a drilling machine

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Noise measurement at a workplace (drilling machine)
Source: IFA

As a result of the Noise and Vibration OSH Ordinance of 6th March 2007 and the new action values defined therein for prevention measures, many businesses perceive the need to carry out supplementary noise measurements at their workplaces. The noise exposure limit conforming to EN ISO 9612 (2009-09) has to be determined as the parameter for assessing the noise situation. This replaces the previously conventionally used assessment level.

The performance of measurements in accordance with EN ISO 9612 is described in plain language and with reference to examples in "Lärmmessung im Betrieb". This paperback publication, dealing with in-plant noise measurements, also compares the different measurement strategies, i.e. task-based measurements (Strategy 1), job-based measurements (Strategy 2) and full-day measurements (Strategy 3). In order for performance of the measurements to be simplified and potential errors to be avoided, model reports are provided that can be used as checklists and worked through step by step for production of the final result.

To calculate the noise exposure level from the measured values LAeq for certain tasks (part times) within a representative working day or working week, a calculation program is available to determine the noise exposure level (in German).

The German Standards Institution (DIN) offers the user of DIN EN ISO 9612 a table calculation program that was developed in conjunction with the revision of ISO 9612. With this table, it is possible to determine the noise exposure level using the three strategies described in the standard and also calculate the associated measurement uncertainties at the same time. Correct use of the program presupposes knowledge of the specifications of EN ISO 9612 (2009-09).

Literature on the topic:

Maue, J.: Lärmmessung im Betrieb . Anleitung zur normgerechten Ermittlung der Lärmexposition am Arbeitsplatz und der Geräuschemission von Maschinen. Erich Schmidt, Berlin 2011 (in German)


Dr Andrea Wolff

Divison 4: Ergonomics - Physical environmental factors

Tel: +49 2241 231-2801
Fax: +49 2241 231-2234