Vent hood noise measurements

9 years ago

Sometimes my husband is brilliant. I was musing about my (replaced) kobe insert and the noise levels thereof and he said "there's gotta be an app for that". And of course there are many apps for measuring noise levels. After some brief research I chose Noisee because it cost .99 and was highly rated for accuracy as reported here http://www.safetyawakenings.com/safety-app-of-the-week-7/
I measured using my iphone 5, in a lifeproof nud case, and had the following results for my Kobe IN2642SQB-1200 (42")

Db at each fan speed follow:
Resting on the rangetop: quietmode 57.2, l 64.9, m 78.8, h 82.4
At the kitchen table 15 feet away: quietmode 50.4, l 57.7, m 70.6, h 73.5

I measured the lowest level, waiting for noise from an outdoor lawnmower, ice maker, water slurping dog, and a child munching his sandwich to subside.

Kobe's specifications are in sones and I don't quite understand how that translates to db:
QuietModeÃ¢ÂÂ¢ 350 cfm (1.6 sones)
Low Speed 475 cfm (2.8 sones)
Medium Speed 900 cfm (7.0 sones)
High Speed 1200 cfm (8.0 sones)

I'm not sure this is useful, but playing with the app was 99 cents worth of entertainment - who knew that the sound of a slurping dog 10 feet away would be over 2 Db?

In general, my house is loud (2 dogs and twice as many children). My subjective experience is that I never mind having the fan on quietmode, and I usually use low, reserving high only for the vigorous boiling of shellfish and medium for the occasional stir fry. The performance is great, and now that the lights and noise are fixed I think I'm going to be entirely happy with the venting.

Here is a link that might be useful: reports on noise app accuracy

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Comments (8)

a2gemini
9 years ago
Wow! I need to get this app to measure my Vitamix!
And I can measure my vent fan as well but I think that is accurate
foodonastump
9 years ago
kksmama - This is quite the coincidence as I was getting set to start an identical thread today! The app I'm using is MultiMeasures by SkyPaw. What stalled me is I wanted to test the app on my iPhone, iPod and iPad to see if I get the same readings so that we can all begin to compare apples to apples.

My measurements from mine were more compact than yours, starting around 70 on UselessModeÃ¢ÂÂ¢ up to a similar 80 on high. I'll definitely load the app to my other devices and post results within the next couple days. Hope others join the fun!
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kksmama
Original Author
9 years ago
LOL UselessModeÃ¢ÂÂ¢, foodonastump! I hope someone who understands more about sound measurement chimes in. I measured the vitamix (cleaning cycle, 400ml of water, one drop soap) and it topped out at 92.5 today. My capresso burr coffee grinder model 565 was 90. No one tries to carry on a conversation when the vitamix is running.

The house wasn't otherwise perfectly quiet; background noise seems to be at least 37db in the kitchen and I couldn't get readings lower than 32 in the bedrooms. Levels up to 60 and even 70 sound "normal" and not bothersome to me. We're going to Denali national park this summer, I'm going to try to remember to both measure AND enjoy the quiet.
kaseki
9 years ago
I assume these measurements were in units of dBA, a weighted scale designed to match one particular human hearing sensitivity curve (c.f. Fletcher Munson).

Note that sound adds linearly, but is reported logarithmically, so if the room measurement without the hood is close to the room measurement with the hood, some mathematical care is needed to find the actual hood sound pressure level.

Anyway, as I (slightly) understand it, most measurements are taken a meter from the device being measured, often averaged over different angles.

For hoods I'd personally like to see the microphone placed at the height of the ears of the 50th percentile human adult, at the distance these ears would be from the hood when the hood placed at its recommended height over a cooktop and the human is a a typical distance from the cooktop and hence form the hood. (This depends on the hood vs. cooktop relationship and I'm sure that this could be standardized.)

The cooktop, counter, and floor would have to be some rigid material simulating the acoustic reflectivity and damping of stone and ceram. Otherwise the room would be anechoic to remove effects that will differ from kitchen to kitchen. A hard wall at the hood/counter back would be added for wall mount hoods.

As for dBA to sones, here are a couple of charts that came up on Google.

http://www.clarkwholesale.net/wp-content/uploads/2012/05/sones-vs-decibels.pdf

https://www.captiveaire.com/CATALOGCONTENT/DOCUMENTS/SOUND%20CONVERSION%20CHART.pdf

kas
a2gemini
9 years ago
My DH is figuring out the best app - he is an OCD retired engineer, so it will take a bit of time.
Great thread and idea!
musicgal
9 years ago
I begrudge every appliance its loudness: the dishwasher, the vent hood, the icemaker.... but never, and I mean never do I begrudge the sweet voice of the powerful VitaMix. Neat app:)
musicgal
9 years ago
I begrudge every appliance its loudness: the dishwasher, the vent hood, the icemaker.... but never, and I mean never do I begrudge the sweet voice of the powerful VitaMix. Neat app:)
cookncarpenter
9 years ago
Fun app! I checked my hood, 1000 cfm remote Prizer.
Low: 64, Med: 69, Hi: 72
But interesting that what I thought was dead silence in our house is around 38-40...?

Vent hood noise measurements

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a2gemini

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Vent hood noise measurements

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a2gemini

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kksmama
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