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Comment by hangonhn | Hacker News Reader

Can you explain more about the walking part? Is it because pedestrians get hit by cars a lot? Otherwise it seems walking should be incredibly safe.

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Transportation safety is generally measured on a distance basis. If you compare one hour of driving vs one hour of walking, then walking is safer, but if you compare the traffic risks of driving a hundred miles and walking a hundred miles, then that's a different story.

This is also kind of silly; the average person doesn't walk 100 miles (say, a week). Extrapolating relative walking safety from 100ft of darting from your office building, across the street, to your lunch spot, out to 100 miles is not actually the same thing as (say) commuting by foot 5 miles each way for 10 days (where the per-step risk profile is probably a lot lower than the numbers we're extrapolating from).

Yeah, agreed. I think you just need to be making apples-to-apples comparisons based on the type of trip.

If you're talking about trips of no more than a few miles (that don't include hauling too much cargo to carry), you can compare driving with walking. If you're talking about trips of tens or hundreds or thousands of miles, you have to compare driving with flying or taking a train.

I would be interested to see crash/injury/fatality stats for car trips under certain distance thresholds. I wonder if those are tracked anywhere.

This is also why the safety of commercial air travel is (sometimes) overstated. Since most crashes happen on takeoff or landing, the risk profile of a 100-mile flight is about the same as for a 1000-mile flight, but on a per-mile basis the latter flight appears safer.

Is this still true for commercial flights? The most prominent airliner losses from the last 20 years were not close to takeoff nor to (scheduled) landing. I'm thinking of Air France off Brazil, the two Malaysian planes, all four 9/11 attacks, and the Germanwings crash. The exception is the Concorde crash on takeoff which just sneaks into the last 20 years (July 2000).

Of course, part of the reason these crashes were newsworthy is that they were unusual. Are there enough takeoff- and landing- related losses to make these statistically irrelevant?

My information may very well be out of date! This is one of those lines I've been repeating for 20 years and it might be time to update it.

On a per journey basis, in Europe/US/Canada, considering _only_ commercial aviation (i.e., excluding general aviation), the fatality/journey rate is comparable to both cars and walking.

Looking at Wikipedia [0], there a a lot of incidents I never heard about and a disproportionate number are "shortly after takeoff".

I didn't count them all, but from eyeballing it a 1000-mile journey is 3x as likely to kill you as a 100-mile one, not 1x or 10x.

[0] https://en.wikipedia.org/wiki/List_of_accidents_and_incident...

Also because when people are contemplating whether to fly the alternative often isn't using another form of transportation but not travelling at all and using video conferencing, or travelling a shorter distance (e.g. going on holiday more locally)

Like some of the other comments already mentioned, its indeed on a per distance basis. Also traffic accidents are far more deathly if you're walking basically naked from a safety perspective vs protected by a well designed mass of metal.

When a car and a human collide, it's not the driver that's likely to die.

I got my stats from https://en.wikipedia.org/wiki/Micromort which shows walking approx 12 times as dangerous per mile.

On a time basis walking would be less dangerous than driving I reckon. Walking also has other health benefits.

I mentioned it specifically, because walking to the store instead of driving for safety reasons would not be a smart choice. Doing some daily walking in a park likely would be a smart choice though.

That depends on many factors. Living in a crowded European city I have plenty of shops in walking distance, protected sidewalks and a traffic nightmare. It would take me longer and I'd be much more likely to get into an accident when driving to any of the shops nearby; walking is easier and safer. If you have a city designed for cars like most US cities seem to be the story is very different.

Per se walking is definitely safer, given decent walking conditions. If all you got are sidewalk-less streets and only big shops that are a decent distance away, that's not the fault of walking but of bad city design. similarly in winter, if there's snow and your city clears the street but not the sidewalk then of course the sidewalk is less safe.

FYI, here's where they get the 12x more dangerous data from:

https://web.archive.org/web/20091122180337/http://www.statis...

Might have something to do with the size of your signature (I think that's what they call it in military terms).

Consider a spherical traveler following a certain path in a field of randomly moving projectiles. The chances of being hit with one depends on path length, your own size, and how long you stay on the field.

Seriousness of the hit depends on your durability and speeds involved.

Maybe pedestrians just spend a lot of time exposed (assuming they have to cover similar distance) and bikers are extra fragile.

My guess is that on a per distance basis, walking is more dangerous because of pedestrian-car collisions (aka getting run over).

I think part of the dissonance is that intuitively I tend to compare on a time basis. I guess it depends on whether one is traveling to a destination (constant distance) or traveling for recreation (constant time).

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