Are There Any Audio Engineers/Knowledgeable People in Regards to Ultrasonic Noise Dog Device Here?

[shasta0863]

Hello,

I'm trying to put myself to ease here, now that an ultrasonic machine for dogs is up. I live in a attached condo so our entry way is attached with a 6ft stone wall in the middle. From upstairs I can see the neighbors entire entry.

My family decided after constant noise abuse from the dog next door (which comes outsides and yelps at the level of a pig screaming) in which the owner refuses to fix. For an idea, at my window on second floor, my db meter (actual meter not a phone) has the dog coming in at 90-95db at my window, sometimes it can reach higher if it really goes off. It bothers my T and my H, no question. No air conditioning means windows are always open, so thus the problem.

Now, a 105-110db 20-22khz dog ultrasound device has been put up just above the middle divider in our entryway so that it points down towards the neighbors entry. I can find little information about ultrasonic noise on humans, as the studies on it are far and few inbetween in seems. There's some that discuss people feeling ill, sick, dizzy, ear fullness ect., but at what level and what range, all vague stuff. I'm concerned as just because you can't hear it, doesn't mean it's not entering the ear and rattling the haricells or causing damage.

Ultrasound works differently than normal sounds, is that correct? Once the sound hits a wall or window, it returns extremely lowered and dissipates much quicker than say normal sounds like music or a loud bang would?

The only information I could really find on limits were wikipedia where it stated:

"The UK's independent Advisory Group on Non-ionising Radiation (AGNIR) produced a report in 2010, which was published by the UK Health Protection Agency (HPA). This report recommended an exposure limit for the general public to airborne ultrasound sound pressure levels (SPL) of 70 dB (at 20 kHz), and 100 dB (at 25 kHz and above)"

Assuming this is correct, that exposure limit is very low at 70db. These devices are outputting 105db, so my concern is whether or not once it hits the neighbors walls/windows a mere 7-8 feet away from the device, will it be coming back another 10 feet at a low enough level to not be worrisome.

My lack of knowledge on how ultrasonic travel and disperse is the problem, so I'm hoping anyone knowledgeable on this issue can bring some insight here.

Thank you~

 

[RaZaH]

20-22 khz is just slightly above human hearing, this high freq is very directional and behaves like light in terms of reflection. Like all sound it will dissipate according to the inverse square law.

I am not familiar with the radiating pattern for such a device , but lets imagine that it were 17-18 khz and you still had the hearing to hear that freq , due to that freq being highly directional you would not hear that freq standing behind a speaker radiating the freq unless you had close reflections.

So the location and radiating pattern of such a device is important , I guess if its not pointing into your window , you should be good.

 

[shasta0863]

20-22 khz is just slightly above human hearing, this high freq is very directional and behaves like light in terms of reflection. Like all sound it will dissipate according to the inverse square law.

I am not familiar with the radiating pattern for such a device , but lets imagine that it were 17-18 khz and you still had the hearing to hear that freq , due to that freq being highly directional you would not hear that freq standing behind a speaker radiating the freq unless you had close reflections.

So the location and radiating pattern of such a device is important , I guess if its not pointing into your window , you should be good.

Thank you for the reply. Just to clarify, ultrasound is very directional (so the sound leaving the device is not like if music was leaving the device) and that once it hits the target it dissipates very quickly? So while Music playing would almost engulf the entry way, this type of sound does not do the same thing.

It's hitting a house wall and windows, so if the sound is more volatile to dispersing compared to lower freq. noises, it theoretically shouldn't be bouncing back anywhere near the 105db its leaving from the device.

Since you seemed informed on this, may I ask why the threshold seems so low on exposure to this sound? Assuming that U.K study was right, 70db for ultrasound seems very low, which makes me assume it's more damaging yet the data on this is very limited from what I found.

Thanks again.