Sound power testing
How much sound does your product actually emit? Sound power is the answer that travels — it is a property of the product, not of the room it happens to be in, which is why regulators and buyers ask for it.
Exporting to the EU? Two deadlines are already running
Machinery Regulation (EU) 2023/1230 applies from 20 January 2027 and replaces Directive 2006/42/EC. It carries forward the requirement to declare emission sound pressure at workstations and, where that exceeds 80 dB(A), the sound power level. Every machinery exporter selling into the EU faces a documentation refresh in the window we are in now.
Directive 2000/14/EC on outdoor equipment covers around 57 categories — generators, compressors, concrete mixers, lawnmowers, chainsaws, pumps, welding sets — and its airborne noise measurement methods were updated by delegated act with effect from 22 May 2025. If your last test predates that, it may no longer be the current method.
Separately, the IEC 60704 series produces the declared noise figures that appear on EU energy labels for air conditioners, washing machines, dishwashers and refrigerators. Thailand manufactures all of these at scale.
| Standard | What ALT does with it | Status |
|---|---|---|
| ISO 3744 Determination of sound power levels using sound pressure — Engineering methods for an essentially free field over a reflecting plane | The workhorse method for machinery noise declarations, including EU Directive 2000/14/EC and the Machinery Regulation (EU) 2023/1230. | Traceable — not in accredited scope |
| ISO 3745 Determination of sound power levels — Precision methods for anechoic and hemi-anechoic rooms | Precision grade 1 sound power in the anechoic chamber, for products where the declared figure has to withstand challenge. | Traceable — not in accredited scope |
| ISO 3741 Determination of sound power levels — Precision methods for reverberation test rooms | Sound power in the reverberation room, suited to broadband sources and products that are awkward in a free field. | Traceable — not in accredited scope |
| IEC 60704 series Household and similar electrical appliances — Test code for the determination of airborne acoustical noise | Appliance noise declarations. The figure that appears on EU energy labels for air conditioners, washing machines, dishwashers and refrigerators. | Traceable — not in accredited scope |
| ASTM E477 Laboratory testing of ducted air distribution systems and air terminals for aerodynamic and acoustical performance | Insertion loss and regenerated noise of silencers and air terminals. | R&D measurement — not accredited |