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Silent cars are dangerous. It’s not extremely dangerous, but we have lots of cars. Consider even very slow speed collisions can be dangerous. People get pinned or pushed into traffic etc.

Comparing even a fairly low number of deaths and serious injuries vs a minor noise from moving cars and it’s an obvious choice IMO.



In my opinion these kinds laws are of the kind that "we need to do something because we need to do something". The effects are marginal. If these laws were the result of solid scientific studies and engineering it would be different, but they are not.

Basically everybody has to pay the price of having more noise pollution to save a few people not paying attention at what they are doing.

The reason we get these kinds rules is because there is a regulatory framework for cars. which makes it easy to add additional requirements.

For example, in the Netherlands both electric mopeds and high speed electric bikes get more popular. Certainly the bikes are at high speed essentially silent (small bike tires have less friction and make less noise).

Because there is no framework to require bikes to make noise they don't have to. And needless to say, a collision with a bike going 45 km/h will do a lot of damage.

If people bumping into silent things was a wide spread problem, then yes it would make sense to require every thing to make noise.

But these types of accidents are just that, accidents. They will always happen. Taking random measures to reduce accidents with an unknown amount will just make society as a whole worse.


> Taking random measures to reduce accidents with an unknown amount will just make society as a whole worse.

It’s not random, actual studies gave demonstrated the risk for years. https://crashstats.nhtsa.dot.gov/Api/Public/ViewPublication/... “The HEV was two times more likely to be involved in a pedestrian crash in these situations than was an ICE vehicle.”

And no it’s not just about people not paying attention, the blind don’t get the option on this one.


That's why it is random. Solid engineering implies that you estimate how much effect this measure will have.

Note that the report says 'Incidence rates provided in this report should be interpreted with caution due to the small sample size.'

If this was solid engineering, there would minimum noise requirements to help people with reduced vision.

This is similar to having a man with a flag walk in front of car. Because those horseless vehicles are just scary.


I was intentionally linking to an early study. There are plenty of studies looking into this issue and more than enough data to determine it’s a real problem. In fact many hybrids have included such systems for years.

Here is a more recent example with far more data. https://www.iihs.org/media/0465243f-89d5-4fa7-95c1-367f1e2c1...

Overall it’s on the order of hundreds more deaths in the US alone assuming every car becomes a hybrid or electric vehicle without these systems.


And even without deaths it's far more comfortable as a pedestrian if I can hear a car coming before I turn my head. Situational awareness as another comment mentioned elsewhere relies on all of the senses. I for one would like more sound from e-scooters; been almost hit a few times.


Personally I'd rather have the environment as free of noise pollution as possible, and I'll just look both ways before I cross the street.


Meanwhile, parking lots turn into a deadly game of frogger...

The average reaction time for humans is 0.25 seconds to a visual stimulus, 0.17 for an audio stimulus. You’re crossing at a crosswalk past stopped cars and someone takes their foot off the break, you will dodge faster with engine noises. And, it’s not just about crossing the street, knowing a car is on changes how people walk past seemingly parked cars.

Worse, saying you will just get this right every single time you do it, however you only need to make a mistake once to die.


I don't want the noise and I don't agree it's necessary.

A claimed 0.08 seconds improved reaction time (were you implying that was a lot? because a slow-moving car doesn't go far in 0.08s) is not enough reason in my opinion to have what are bound to be deafening beepers everywhere. So noise! much safety! You are proposing a ridiculous noisy dystopia. Imagine a carpark full of cars loudly beeping at all times!

Cars should have sensors like parking sensors for when they're moving slowly, or flashing lights, or literally any other solution than more meaningless noise in our already much too noisy environment.

You are overstating the danger with your, "you only need to make a mistake once to die" alarmism.


The study you linked is pretty interesting. They attempt to control for the variables by only studying cars with highly similar models of hybrid and non-hybrid variety. They show a 17% increase in the number of bodily injury claims without a corresponding property damage claim. They do disclaim that they can’t actually tell from this data if a pedestrian was actually involved.

But I wonder if there’s one thing missing here. Hybrids have a lot higher low-end torque. I think the definitive study would be on a hybrid car with and without the noise, and I’m not sure if they ever tried to do that for the Leaf?


It’s hard to put a value on what lowering ambient sound levels in a city might be worth. Or overall even how many lives it could save. Or productivity and wellbeing increases due to lower stress levels.

A minor noise from moving cars? How about this horrifying little marketing piece from Nissan [1] about their new “Canto” noise they are going to emit?

Besides, these noise levels are calibrated to be loud enough in a bustling city at high noon. They are not dynamic based on time of day, or location, or actual ambient sound levels. So, in other words, they will be loud and obnoxious, particularly outside of the city, where ambient is almost 20dB lower.

[1] - https://youtu.be/p4cjPk8mqEM




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