Page 50


www.us-tech.com


September 2025 Sound Measurement of Fume Extractors By Gerald Gardener, Global Product Manager, Weller Tools F


ume extractors are essen- tial tools in environments where harmful airborne


particles and vapors must be removed to protect users and maintain air quality. They are commonly used in electronics manufacturing,


laboratories,


dental clinics, soldering stations, and light industrial applications. While filtration efficiency and safety standards are key per- formance metrics, another cru- cial factor is often underestimat- ed: noise. Low noise levels are vital in


professional workspaces where concentration and communica- tion are critical. Excessive noise can lead to fatigue, stress, and reduced productivity. For users working long hours next to fume extractors, quieter operation con- tributes directly to well-being and comfort.


Understanding dB and dBA Sound is measured in deci-


bels (dB), which quantify sound pressure levels. However, not all frequencies are perceived equal- ly by the human ear. To account for this, the dBA (A-weighted decibel) scale adjusts measure-


Weller’s new Guard series units were tested in a certified acoustic laboratory.


mic, meaning every 10 dB increase represents a tenfold increase in perceived sound intensity. For example:


l 50 dBA is 10 times louder than 40 dBA.


lIf two identical sound sources are running simultaneously, the combined sound level increases by approximately 3 dB.


Therefore, combining two 50


dBA sources will result in 53 dBA, not 100 dBA. This principle becomes important when multiple


location, typically 1 meter from the source. When sound disperses uni-


formly in all directions (spherical propagation), its intensity dimin- ishes with distance. The inverse square law states that for every doubling of distance, the sound pressure level drops by 6 dB. Example: If a source has an


LpA of 60 dBA at 1 meter, at 2 meters it will measure approxi-


mately 54 dBA: LpA (2m) = LpA(1m) –6, therefore 60 dBA –6 = 54 dBA


ments to reflect the audible spec- trum more accurately — empha- sizing frequencies humans hear best (around 2,000 to 5,000 Hz) and de-emphasizing very low and high frequencies. The dBA scale is logarith-


units operate in the same room. Sound power level (Lw) rep-


resents the total energy emitted by a source and is independent of distance. Conversely, sound pressure level (LpA) is what is actually measured at a specific


Certified Testing and Standards


Weller’s new Guard series


units were tested in a certified acoustic laboratory in accordance with:


l DIN EN 60335-1: Safety of household and similar electrical appliances.


l DIN EN ISO 3744: Determination of sound power using sound pressure in free- field over a reflecting plane.


l DIN EN ISO 11201: Measurement of noise emitted by machinery at the operator position.


l DIN EN ISO 7779: Acoustics measurement for office equip- ment.


These standards ensure that


measurements are reliable, repro - ducible, and representative of real-world conditions.


Sound Testing Environment The acoustic testing lab fea-


tures an anechoic chamber designed to minimize reflections. It includes multiple calibrated


Continued on next page


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80  |  Page 81  |  Page 82  |  Page 83  |  Page 84  |  Page 85  |  Page 86  |  Page 87  |  Page 88  |  Page 89  |  Page 90  |  Page 91  |  Page 92  |  Page 93  |  Page 94  |  Page 95  |  Page 96