One standard, two numbers
Any sander maker selling in Europe declares noise to EN 62841-2-4, the part of that standard family covering handheld sanders and polishers. Two quantities come out of it. LpA, measured at the operator's position, stands for what the person sanding hears; LWA is sound power, the total a sander gives off into the shop. K, the uncertainty, is usually 3 dB.
The sanders here are in order by LpA, with each one's LwA alongside. Festool's ETSC 125 gets 68.00 at the ear and 79.00 sound power from the same test, two different measures that never share a ranking, and the gap between a sander's power and pressure numbers gets a fuller treatment elsewhere.
What is the quietest orbital sander?
Festool's cordless ETSC 125, at 68.00 dB(A) at the ear and 79.00 sound power. Festool takes the top four places.
Every Festool sander is declared on the international site, with both quantities, the K value and the standard. The US sander pages reproduce those tables minus the noise rows, for reasons Festool does not give, and the US operating instructions we opened for the ETS 125 REQ carry no declaration either.
The Festool figures here are therefore the international ones, with each US article number paired to its international twin. Names, motor power, speed range and weight all match between the two pages. Every Festool sander figure, though, was declared for a 230 V tool, and the US sanders run on 120 V.
| Festool sander | At the ear | Sound power |
|---|
| ETSC 125 (cordless) | 68.00 dB(A) | 79.00 dB(A) |
| ETS EC 125/3, EC 150/3, EC 150/5 | 69.00 dB(A) | 80.00 dB(A) |
| ETS 125 REQ | 73 dB(A) | 84 dB(A) |
| ETSC 2 125 (cordless) | 74 dB(A) | 82 dB(A) |
| ETSC 2 150 (cordless) | 76 dB(A) | 84 dB(A) |
Stroke length made no difference in Festool's tests: the three brushless EC sanders, with 3 mm and 5 mm strokes, all declare 69.00 and 80.00.
Every 5 and 6 inch Mirka DEROS II declares 71 dB(A) at the ear and 82 sound power with a K of 3.0. No other maker here prints the full declaration for the exact tool a US buyer gets: the DEROS II manual for the US, Mexico and Canada covers the 110 V 350X, 550X, 625X, 650X and 750X.
Mirka's US pages repeat a 71.0 dB noise level and list Mirka's prices too, $616.41 for the 550X or 650X without a case and $701.45 for the 625X.
Metabo's page and manual disagree
Few makers put sander noise on a US product page. Metabo does, and the page and the manual give different numbers.
For the 5 inch SXA 18 LTX 125 BL the US page gives 70 dB(A) at the ear, while the manual, declared under EN 62841-2-4 for the same serial number, gives 67. For the 6 inch SXA 18 LTX 150 BL the page gives 89 and the manual 86. Both gaps are exactly the K value, and the two documents also disagree on weight and vibration.
The ranking uses the higher figure, the one on Metabo's US page. That puts the 125 BL fifth at 70 and the 150 BL last at 89.
Makita's US page for the corded BO5041K links a manual declaring 81 dB(A) at the ear and 92 sound power, K 3, under EN60745, the older standard that EN 62841 replaced. The US manuals for its BO5031K, BO6050J, cordless XOB01 and BO4556K palm sander carry nothing.
Festool's gear driven ROTEX RO 150 is a different kind of machine, with a rotary mode for fast removal. In every mode it is rated 85 dB(A) at the sanding position and 96 of sound power, 17 decibels above the ETSC 125.
Two other guides cover the rest of a sanding setup. For stripping paint and levelling glued up panels, our belt sander guide ranks ten declared under the same standard, and our guide to dust extractors covers thirteen with maker noise figures.
Which popular orbital sanders have no noise rating?
Bosch, DeWalt, Milwaukee and RYOBI print no figure for their best-selling US random orbital sanders, so none of them can be ranked.
Bosch prints no noise in the US manuals for its ROS20VSC corded sander or GEX18V-5 battery sander. DeWalt's US manuals leave it out too, for the DCW210 battery sander and the DWE6420, DWE6421 and DWE6423 corded sanders. Milwaukee prints none in the manual for its M18 2648, and RYOBI's US page for its 18V ONE+ 5 inch sander shows no figure. These are some of the best selling sanders in the country.
How loud any of them runs is anyone's guess.
