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Comment by flashman | Hacker News Reader

> Airflow is necessary to keep passengers safe.

This has just made me wonder what happens in emergencies or system failures. Are the tunnels wide enough to open your door or climb out a window? How far apart and numerous are emergency exit hatches? Is there off-grid emergency lighting (e.g. battery-backed)?

There would be few things more upsetting than your sled coming to a halt, inside a dark tunnel, and being unable to get out of your car. It would activate the same part of your brain that fears being buried alive.

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Air isn't really a problem. A person breathes about .5 cubic meters of air per hour, so 100 people trapped for 6 hours will go through 300 cubic meters of air. The diameter of the tunnel being 14', that air supply would take up 68' of tunnel lengthwise. And that's one breath, the air can be breathed many times before the co2 level becomes too high.

The air inside the volume of a coffin can last you a few hours. Unless you are literally shoulder to shoulder with no other air, your oxygen will last as long as you need.

I know that. I also know that I'd probably panic in that situation.

"The air inside the volume of a coffin can last you a few hours. Unless you are literally shoulder to shoulder with no other air, your oxygen will last as long as you need."

... unless there is a fire:

"Most drivers rolled up their windows and waited for rescue. The ventilation system in the tunnel drove toxic smoke back down the tunnel faster than anyone could run to safety. These fumes quickly filled the tunnel and caused vehicle engines to stall because of lack of oxygen. This included fire engines which, once affected, had to be abandoned by the firefighters. Many drivers near the blaze who attempted to leave their cars and seek refuge points were quickly overcome."[1]

[1] https://en.wikipedia.org/wiki/Mont_Blanc_Tunnel#1999_fire

Wow the aftermath of that sounds like a witch hunt.

As niche as it might be, sounds like another point in favor of EVs no?

In that case ventilation was the cause of those deaths, or at least made the situation worse. It doesn't have much to do with the availability of oxygen.

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