Accredited Acoustic Power Determination
Acoustic power (sound power level, LW) is the parameter describing the total acoustic energy emitted by a machine — independent of the environment in which it operates. Under Machinery Directive 2006/42/EC, manufacturers are obliged to declare sound power levels in technical documentation and operating instructions. OIKOS determines sound power levels based on sound pressure measurements per the EN ISO 3740–3747 series, under PCA accreditation No. AB 934 (PN-EN ISO/IEC 17025) — results recognised by notified bodies and EU market surveillance authorities.
Why OIKOS for Acoustic Power Determination
Four reasons our acoustic power determination stands out — CE-ready documentation backed by EN ISO methods:
- AB 934 accreditation covers acoustic power level determination — results recognised by notified bodies and market surveillance authorities in the EU
- Acoustic power level is environment-independent — measured once, valid for every installation of a given machine model
- Results provide data required for CE declaration of conformity, operating manuals and tender specifications under the Machinery Directive
- 35+ years of acoustic measurement experience, part of the viridiusLAB AG network — European comparability of results
EN ISO 3740–3747 — Reference Methods for LW Determination
OIKOS determines sound power levels based on sound pressure measurements performed in accordance with the applicable standards of the EN ISO 3740–3747 series. Measurements are conducted under controlled conditions or at the machine’s installation site, and results are documented in an accredited report under AB 934.
Acoustic power level (LW) is the parameter describing the total acoustic energy emitted by a machine, regardless of the environment — making it a comparable and repeatable parameter, required by the Machinery Directive 2006/42/EC for technical documentation, operating instructions, procurement specifications and noise risk assessments.
OIKOS has been performing accredited acoustic measurements for over 35 years. As part of the viridiusLAB AG network, we participate in European interlaboratory comparison programmes, ensuring comparability of our results with laboratories throughout Europe.
Methods & Instruments
Methods
Sound power level determination of machinery using measurement methods (Grade 2, 3) per EN ISO 3744 and 3746.
Instruments
Class 1 sound level meters, acoustic calibrator, tripods, measurement microphones, A-weighted sound power calculation software.
Reference documents
EN ISO 3744:2010; EN ISO 3746:2010; Machinery Directive 2006/42/EC; Polish MoE regulation on essential requirements for machinery.
FAQ
Acoustic Power Questions
What is acoustic power and how is it different from sound pressure level?
Sound power level (LW) describes the total acoustic energy emitted by a source and is a property of the machine itself — independent of distance or the acoustic characteristics of the environment. Sound pressure level (LP) is a value measured at a specific location and depends on distance from the source, room geometry and absorption conditions. Acoustic power is required for machine technical documentation because it is comparable and reproducible.
When is acoustic power measurement of a machine required?
Acoustic power measurement is primarily required when obtaining CE marking for machinery and equipment (Machinery Directive 2006/42/EC) and when preparing noise emission declarations for public procurement specifications and tenders. It may also be required in noise risk assessments at workplaces and in the design of acoustic protection for industrial installations.
Is acoustic power measurement needed for CE marking?
Yes. Machinery Directive 2006/42/EC requires the manufacturer to declare the sound power level LWA in the machine’s technical documentation and operating instructions where the emitted sound pressure level at the operator’s workstation exceeds 70 dB(A) or the peak level exceeds 63 Pa. An accredited report on LWA determination, issued by an AB 934 laboratory, constitutes the required documentary basis for this declaration.