Dishwasher-makers aggressively tout the quietness of their dishwashers by dBA ratings. A dBA rating expresses a weighted decibel level that puts in human context to how loud or quiet a sound is to our ears, because humans perceive sound differences less sensitively at volume extremes. With dishwashers in the marketplace ranging from 37-64 dBA, what really matters when it comes to quietness and what’s simply hype?
We speak at about 60 dBA, light rainfall registers at 50 dBA, a quiet suburb at night registers at 40 dBA and a whisper registers at 30 dBA. Check out Bosch’s interactive “Understanding Decibels” feature on its website to better understand common noise levels.
Dishwashers used to average about 65 dBA. Now, the majority of dishwashers have dBA in the low 50s to the 40s, so somewhere between dinner table chatter and scattered showers. Not only is that a vast improvement over what you likely have in your kitchen, but I bet it will clean way better too.
The most quiet dishwashers compete on just one or two dBA levels — a difference that is unnoticeable or barely so. The Miele Futura Diamond dishwasher comes in at 37 dBA when used in its Extra Quiet Program mode; otherwise, it’s rated at 42 dBA. The Bosch 800 Plus comes in a close second at 38 dBA “in normal operation,” which I think means with clean dishes.
Miele explains that dirty dishes often lead to louder operation in competing brands, because the dishwasher has to work harder than during testing. The lowest difference between testing its competitor’s dBA claims using both clean and dirty dishes was about 3 dBA levels, which is barely noticeable.
In the real world, we call this splitting hairs, so such a slight difference should not be your deciding factor. Alternatively, you will likely notice 10 dBA levels, which is the point at which audible sound doubles.
However, how quiet does your dishwasher really need to be not to interrupt your life? Current trends in home layouts have kitchens much more open to the rest of the house, but what the dBA levels don’t remind you of is that sound dissipates with greater distance.
Are you home-schooling your children at the counter or for some strange reason installing a dishwasher in your nursery? If you’re not carrying on important tasks near your dishwasher, take the ratings with a grain of salt and consider price, racking and performance as also very important.