[YossarianFrPrez]

Some days I joke that there should be a set of Nobel prizes for making machines quieter. Categories could include: air-conditioning units and mini-fridges, construction and landscaping equipment, old university buildings, pump-housings, etc. The quality of life of many would be improved if we had quieter machines. It boggles my mind that a) in many hotel rooms one can hear a good deal of machine noise and neighbors' televisions, and b) that some sort of noise score (as calculated from DB meter measurements) isn't more widely available for things like apartment rentals, conference room bookings, etc.

[willsmith72]

what about a noise tax? my city has some electric buses and some ancient buses - the difference obviously is absolutely huge, but right now the financial incentives aren't there to upgrade the whole fleet

[sidewndr46]

Noise from construction machines is actually a feature. They all have added backup beepers at this point as required per OSHA guidelines. Audible for well over a mile in normal conditions

[arp242]

> Audible for well over a mile in normal conditions

That doesn't strike me as a feature.

Also a solved problem: https://www.youtube.com/watch?v=6rwJ5NCf1Vw

Tesco delivery trucks have them here in Ireland; it's pretty good stuff. Still quite loud/noticeable when you're up close, while at the same time not being completely obnoxious to everyone in a kilometre radius.

[sidewndr46]

They have to be loud enough to be heard through hearing protection. The amplitude is a feature.

It's a "solved problem" in the sense that nuclear energy is a solved problem. There's no mandate to actually see widespread roll out of anything that may be a better solution.

There's a construction site near me at present. There is always 1 machine in reverse, at all times. The utility of having a backup beeper or any noise making device on that site is thus zero. It is the single largest source of noise pollution, larger than the roadway

[bumby]

>The utility of having a backup beeper or any noise making device on that site is thus zero.

This strikes me as an odd take, maybe from someone who has never worked on a construction site.

Our auditory sense is more than just a binary “present/not present” detection. We can sense distance and direction. Just because there is a backup beeper somewhere on site does not mean there is no value to any other auditory signal.

Think about when you’re in a congested city. There’s probably a lot of ambient car noise, including horns, in the background. That doesn’t mean you’re unable to react to a honking car in your immediate vicinity.

[sidewndr46]

You just believe you can sense the direction of loud noises in urban environments. Our nervous system has no "404 not found" for positional awareness. Even after severe head trauma, you have a sense of position for everything. It's so wrong as to be useless, but you have it.

Ask anyone who's been at a shooting in a city. Everyone gives a different answer for where the shooter was at. It's such a severe issue the US Army has microphone arrays they equip urban combat vehicles with. Even with bullets actually bouncing off the armor the troops cannot accurately locate the direction of the shooter(s).

[bumby]

As the other poster mentioned, the characteristics of sound matter. That’s why the report of a firearm is a bad example.

But there are more commonplace examples. Older phone ringtones are often hard for people to locate, but nearly everybody can pinpoint the sound of a dropped coin. Sound perception is more complex than just perception of pressure levels. To the point above, you wouldn’t confuse a car honking in front of you with one behind you even in the presence of ambiguous ambient noise.

[tomn]

Bullets are a bad example because they have multiple properties which makes them much harder to localise than many other sounds.

I'm pretty sure most people can localise a vehicle emitting broadband noise (engine or white reversing sound) in the conditions that matter.

[tomn]

> They have to be loud enough to be heard through hearing protection.

It's kind of a nit-pick, but this is not really true.

Very approximately, you will perceive a sound if it is above your threshold of hearing, and also not masked by other sounds.

If you're wearing the best ear defenders which attenuate all sounds by about 30dB, and you assume your threshold of hearing is 10dBSPL (conservative), any sound above 40dBSPL is above the threshold of hearing. That's the level of a quiet conversation.

And because your ear defenders attenuate all sounds, masking is not really affected -- the sounds which would be masking the reversing beepers are also quieter.

There are nuances of course (hearing damage, and all the complicated effects that wearing ear defenders cause), but none of them are to the point that loud reversing noises are required because of hearing protection -- they are required to be heard over all the other loud noises on a construction site.

> The utility of having a backup beeper or any noise making device on that site is thus zero.

The inverse square law says otherwise; on site the distances will be much more apparent.

[gowld]

Those beepers should be directional. I don't need to hear the beep opposite the direction of movement.

[sidewndr46]

The requirements are that it be heard in all directions, including straight up.

[Dambalala]

https://www.quietmark.com/

[stronglikedan]

> making machines quieter

It's already possible, just not profitable.

[mrexroad]

Exactly. That’s where the other comment about a “noise tax”, or enact fines for exceeding limits, are probably necessary to shift the calculus.

Japan is a good case study [1]. If nothing else, it’s fun to look at the charts showing noise reductions—not just in aggregate, but for each contributing input (e.g. engine, intake, exhaust, tires, cooling)—for both passenger vehicles and heavy equipment. Unfortunately, in the US, we have a few obstacles to legislation like this, least of which being public apathy as majority of voters who are not exposed to high sound levels daily.

“Japan's primary legislation governing noise regulation is the Environmental Noise Regulation Act, first introduced in 1986 and subsequently amended in 1999. This act sets different noise limits for different times of the day, with the maximum allowable noise level during the day set at 55 decibels and reduced to 45 decibels at night to prevent disturbances to those who are sleeping. Violators of these standards are subject to penalties.”

[1] https://www.lios-group.com/news/noise-regulations-in-japan-o...