While all impact drivers are loud power tools, they’re not all the same. Some impact drivers are comparatively quiet, whereas others are so loud you’d rather hear your alarm waking you up at 5 a.m.
When we set out to design our noise testing methodology, we first searched online to see if there was a single resource from manufacturers or third parties that measures noise performance similarly across brands for reliable comparisons. We found a complete lack of resources, which is why we set off to change things for the better.
Our goal with any of our testing methodologies is to standardize testing across brands to provide apples-to-apples comparisons, especially in key areas where no such information is currently available.
Our noise tests fill this gap and provide our community with supplementary data points that are helpful in determining the best impact driver.
Below, we discuss in detail how we test noise output and why it matters. You can also check out our impact driver noise test results to compare our lab results for all models in our test fleet.
What we test
We test the noise output of each impact driver in our test fleet in a no-load and impacting scenario.
How we test it
We use the DecibelX mobile application on an iPhone to measure noise output. Measurements are completed in our lab where ambient noise is minimal.
Measurements are taken with a 0.2ms response time using an A-weighted decibel curve, which more accurately approximates the way the human ear hears sounds than other decibel curves.
In our no-load noise tests, each impact driver is run for five seconds, and the max, not peak, dBA is recorded as the final result.
We measure noise output when impacting during our driving speed tests. This approach produces practical results users can expect when completing the most demanding heavy-duty tasks.

Why it matters
Noise when impacting is more important to pay attention to than the no-load noise performance since the former most closely represents the most noise an impact driver will produce.
Noise is important to consider for several reasons. Firstly, all impact drivers we’ve tested produce more than enough noise to be harmful with prolonged exposure. This outcome is why wearing ear protection is important, especially for professionals with constant exposure to the noise impact drivers produce.
Around the home, noise output can be more of a consideration for your neighbors and others within your household, though hearing protection is equally important. Models with low-impacting noise are also more pleasurable to use, typically since they offer a smoother experience that is less violent than louder models.
While all impact drivers are harmful with prolonged exposure, certain types are considerably quieter. Hydraulic impact drivers use an oil-impacting mechanism to generate impacts, resulting in less violent and far quieter impacting noise than more common anvil-based hammer-impacting mechanisms. Milwaukee offers several exceptional hydraulic models, including the Milwaukee M18 Fuel Surge 2760-20 and Milwaukee M12 Fuel Surge 2551-20.