Driving While One Window Down Caused a Spike

I had to drive my car with one window down due to malfunction. I was wearing ear plugs so I didn't realize the loud noise and throbbing noise it was making.

I drove for 10 minutes on the street. Today I am having a spike and I can hear my tinnitus over conversations and even while watching TV.

All I had to do was roll down my second window and this throbbing noise would have completely gone.

I read online that when one window is open it creates LOT of pressure inside the cabin.

I feel like an idiot for not pulling over or rolling down second window.

How careful can we really get?? This is so frustrating.

Any idea how loud it would have gotten inside cabin? I was driving for 10 mins at 35-40 mph.

 

I used to drive more 2 hours each day (50km/h max) with one window down (not my side, the other)

It does ABSOLUTELY NOTHING.

 

i read online and there are lot of articles stating it creates very very loud noise and DB level does up to 130-140 DB!!. I was driving only at 35-40 mph so i am sure it was not as loud.

 

Certainly not anywhere close to that.
I'd be very suprised if it would go over 110 dB, even at highway speeds.

I suppose 90 is possible with your speed.
But it's all a guess.

Try to relax, take NAC,MG, and give your ears rest.

 

i just across a study and it showed how loud it gets when you keep one window down. I am trying to look for ir again if i find it, i will post if here.

 

Bullshit, I tried a sound level meter : 60-70dB

I didn't try on an highway, only at 50km/h in the city.

Don't focus on "studies".

You know, walking on a street in the city, taking the subway... are louder than driving with windows down at low speed.

BUT it's OBVIOUS that if you think it's dangerous and you go on the internet finding studies proving that you're right, then it will increase because you're convinced it will.

 

90's kid. I hope you are right.

Did you try with one window all the way down? Thanks

 

I call bullshit. My car is overy 70db inside on a normal road with windows up.

Also, I don't know what km/hr means. I'm an American.

 

Yep, 2 days ago.

 

@90skis. may be i am just panicking. Please do let me know if one window was all the way down and DB level was only 60-70.

 

Around 32 mph windows down and it was 60-70 dB.

I tried windows up at 75 mph and it was 73 dB.

 

This summer, Postmedia’s Tom Spears brings you the often offbeat science behind the season that calls us to go outdoors. It’s all part of a series we call the Science of Summer. Today’s story is on why the open rear window of a car can make your ears hurt while you’re driving.

If you’ve ever turned your head on the highway to yell at someone to close the back window, a physicist in Waterloo has an explanation for why the experience hurts your ears.

Much of the sound from the open rear window is outside the range of human hearing. But it’s still a powerful force battering your eardrums, says John Vanderkooy.

And it’s all because your car acts like an empty pop bottle, when you blow across the bottle to make a musical note.

Vanderkooy studies sound at the Audio Research Group of the University of Waterloo, so I asked him about this.

“I’ve actually measured the noise level in cars, but I have stayed away from the noise level from opening the back window because that is such a high level, and so unpleasant, that people don’t leave it (open.) They always close the window,” he said.

Later, intrigued, he took off in an elderly BMW loaded with microphones to measure it.

“It’s infrasound” — meaning a note too low for us to perceive it as sound — “but it actually presses on the ear so hard that it causes an oppressive feeling,” he explained.

“It’s changing the air pressure. It’s basically the same thing as blowing across the top of a Coke bottle.”

In both cars and bottles, air is flowing across the only opening in an object filled with air. Air flows in through the hole, but the air already inside the car (or bottle) acts like a spring to push the new air back out. But inertia carries too much air out. More comes back in.

“The air is … going into and out of the car,” the professor said. “It is oscillating back and forth. The airstream, as it comes by the window, will send an eddy into the car and then pull air out and then put it in and out again, so it flagellates back and forth.

“It’s a very powerful thing.” He calls it a “pulsating” effect.

There’s also a technical name for it: a Helmholtz resonator, named for the 19th-century German physicist who designed and studied sound in chambers with one hole. Go on, tell your friends you drive one of these.

But if you open a second window, the effect goes away “because that represents an alternate exit for the Helmholtz resonator, so it takes away the strength of the oscillation.” In other words, air can escape out the second window, rather than going back and forth through only one.

With air cycling in and out fewer than 20 times a second, the sound has such a low frequency that we do not hear it in the normal sense. It’s like a note too far past the left end of the piano keyboard.

“You will experience it with your ear but it’s not audible in the normal sense of the word,” Vanderkooy said.

“You can still feel it in your ears if it’s loud enough, and it’s certainly loud enough when you roll down the rear window.”

The empty soda bottle’s air vibrates faster — a few hundred times per second — so we can hear that clearly as a musical note.



Driving with the front window open doesn’t cause the painful pulsating effect because the air flow is different. Vanderkooy says air flow past the rear window is smooth. Meanwhile air flow at the front window is swirling and “confused” because it is filled with eddies flowing off the windshield. But it’s still uncomfortable.

But the professor wasn’t done when the initial interview ended. That’s when he volunteered to do some measurements, taking his car (a 1992 BMW 325i sedan) for a 100-km/h spin with one rear window open, and instruments packed inside.

What he found surprised him.

First, although humans can’t truly hear that rear window noise, it certainly is powerful: it hits peaks of pressure of 100 pascals, equivalent to 130 decibels. There’s a good reason why our ears can’t stand it for long.

Second, he expected to find a disorderly pattern to the air flow from the rear window but instead found a very regular, pulsating one, “even though the ears think that it is quite distorted, presumably due to overload in the ears themselves.”

The frequency was a little less than 20 hertz (while the two lowest notes on a piano are both in the high 20s.) The frequency did not change as he made the window opening larger or smaller.

Vanderkooy also measured what happens with only a front window open: Again it can get loud but the pattern doesn’t cause the regular pulsating of the rear window.

His full title is impressive, by the way: distinguished professor emeritus in the physics and astronomy department at Waterloo.

tspears@postmedia.com

twitter.com/TomSpears1


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Ok.

 

I am having spike after this car window incident ..my god it really sucks to be in this situation . I hope it subsides .

 

I drive pretty often with the windows down. With my handheld meter it is often a few dBs above the noise level with windows up (around 75 on paved road highway speed). It is nowhere near 100dB. not even close to 90.

I wouldnt worry about it. I think the spike is cause by anxiety.

 

I mean only one back window down ..don't even try it . Again one back window down .

 

Lot of people cruise with only one window down in a car.

If this causes hearing damage in the 10 mins that you said you were exposed to it. I think half the world would have hearing damage by now

 

I hope you are right

 

If someone thinks that is good to use ear protectors what kind of them should be good for using while he is in car driving with or without one window down? Does someone here use silicone protection earplugs ?

 

Yes I have an spl lab meter and we got 136.8 Dbs at 17hz

 

This is why it hurts your ears ... idk if you know about car audio but 136 dbs at 17 hz is wicked

 

Hey. Today I went down the road to the suburbs to my grandmother. Suddenly a car drove along this road. At the helm there was, apparently, some fool. The car was without a muffler and loudly rumbled. Thus, the pruning underfoot trembled. After that, I rustled in my right ear. Do you think this is dangerous?

 

They actually do, but they are lucky enough that they don't buzz yet.

 

If it caused a spike, most likely it will go back down. Do anyone think driving on the highway, with window down can cause further damages like hearing loss?

 

Possibly the trigmenal nerves in your face were affected by the wind and they can cause many problems. If I stroked the side of my face it would make my ears buzz! Because those nerves which run through the centre of your brain come through the ear and jaw and into your face and branch out to the eye, nose and chin. During a migraine my trigmenal nerve is extremely painful.