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So those are much smaller tunnels than usually used for both trains and cars as far as I understand. How are the fire safety issues handled here? Large tunnels

So those are much smaller tunnels than usually used for both trains and cars as far as I understand. How are the fire safety issues handled here? Large tunnels usually have a smaller escape tunnel at the side. That doesn't seem to be the case here. Do regulations that mandate escape routes in tunnels not exist in the US? Or are these tunnels different enough that they don't apply? Or do they have safety measures that are not visible on the images here?

jcranmer 3y ago
> Do regulations that mandate escape routes in tunnels not exist in the US? As far as I'm aware, not only do they exist, they are more stringent than in Europe generally. So I don't know how these things are working under US fire codes.
HillRat 3y ago
The current tunnel conforms to NFPA 130, which is intended for passenger rail and mass transit (whether a bunch of passenger cars counts as this is an interesting question), and is less-stringent than federal vehicle tunnel requirements. Essentially, the key requirements here are that you need to have no more than 2,500 feet (760 meters) between exits and cross-tunnel passages no more than 800 feet (245 meters) apart. In the case of the LV "loop," it's a single tunnel shorter than 2,500 feet, so they basically don't need tunnel egress; having said that, imagine an electrical fire in a crowded tunnel with hundreds of tourists in varying degrees of intoxication trying to get out using narrow, 3-ft passages on either side of the cars. It's ... concerning.
- jandrese 3y ago
  > narrow, 3-ft passages Is this a "fat Americans" joke? If it were 1 or 2 foot wide I could see calling it narrow, but 3 feet is plenty wide. Doubly so because there are passages on either side so it's 6 feet of walkway. The low maximum capacity of the system also helps in this regard, it will never need to evacuate thousands of people at once. Just the handful that were in the cars at the time. This might change if Tesla changes out the current cars for higher capacity ones, but it doesn't seem like it should be an issue currently.
  - deleted 3y ago
    [deleted]
  - rmccue 3y ago
    > Is this a "fat Americans" joke? If it were 1 or 2 foot wide I could see calling it narrow, but 3 feet is plenty wide. The standard width for walkways per NFPA 130 is 3.75 ft, so 3 ft is definitely narrower than the US standard. (The European standard (SRT TSI) is 2.6 ft though.)
  - s1artibartfast 3y ago
    Weird take, 3 feet is still quite narrow. at 2ft wide, most people would not be able to walk down it and have to turn sideways, let alone evacuate. The 95th percentile male hasshoulders ~23 in wide, and eblows protrude further.
nerdix 3y ago
If you've seen videos of the current Vegas loop, it looks like a deathtrap. IIRC, there are sections of the tunnel where there isn't even enough space to fully open the car's door. Even if there was an escape tunnel, you might not be able to get out of the car to get to it.
- martythemaniak 3y ago
  Completely false. There are no "sections" of the tunnel, it is all one uniform width. There is 3ft on each side of the car, which is more than most garages and parking spaces.
jccooper 3y ago
NFPA requirements for road tunnels is an emergency exit every 1000ft/300m. Cross-passages to another tunnel are acceptable, including a parallel travel tunnel if there's automatic traffic control. They may also be stairs or ramps. Secondary tunnels are not common; typically they are for long and/or deep tunnels. Dunno if the Vegas system would qualify as a road tunnel (thus NFPA 502) or some sort of transit tunnel, which might be a different thing. (I've not seen such exits provided in subway tunnels; emergency procedure seems to be "walk back to the station".) But in a short shallow system like in Vegas, they could have periodic cross-passages or stairs to the surface. Dunno if they do; never been in it.

jcranmer 3y ago

> Do regulations that mandate escape routes in tunnels not exist in the US? As far as I'm aware, not only do they exist, they are more stringent than in Europe generally. So I don't know how these things are working under US fire codes.

HillRat 3y ago

The current tunnel conforms to NFPA 130, which is intended for passenger rail and mass transit (whether a bunch of passenger cars counts as this is an interesting question), and is less-stringent than federal vehicle tunnel requirements. Essentially, the key requirements here are that you need to have no more than 2,500 feet (760 meters) between exits and cross-tunnel passages no more than 800 feet (245 meters) apart. In the case of the LV "loop," it's a single tunnel shorter than 2,500 feet, so they basically don't need tunnel egress; having said that, imagine an electrical fire in a crowded tunnel with hundreds of tourists in varying degrees of intoxication trying to get out using narrow, 3-ft passages on either side of the cars. It's ... concerning.

jandrese 3y ago
> narrow, 3-ft passages Is this a "fat Americans" joke? If it were 1 or 2 foot wide I could see calling it narrow, but 3 feet is plenty wide. Doubly so because there are passages on either side so it's 6 feet of walkway. The low maximum capacity of the system also helps in this regard, it will never need to evacuate thousands of people at once. Just the handful that were in the cars at the time. This might change if Tesla changes out the current cars for higher capacity ones, but it doesn't seem like it should be an issue currently.
- deleted 3y ago
  [deleted]
- rmccue 3y ago
  > Is this a "fat Americans" joke? If it were 1 or 2 foot wide I could see calling it narrow, but 3 feet is plenty wide. The standard width for walkways per NFPA 130 is 3.75 ft, so 3 ft is definitely narrower than the US standard. (The European standard (SRT TSI) is 2.6 ft though.)
- s1artibartfast 3y ago
  Weird take, 3 feet is still quite narrow. at 2ft wide, most people would not be able to walk down it and have to turn sideways, let alone evacuate. The 95th percentile male hasshoulders ~23 in wide, and eblows protrude further.

nerdix 3y ago

If you've seen videos of the current Vegas loop, it looks like a deathtrap. IIRC, there are sections of the tunnel where there isn't even enough space to fully open the car's door. Even if there was an escape tunnel, you might not be able to get out of the car to get to it.

martythemaniak 3y ago
Completely false. There are no "sections" of the tunnel, it is all one uniform width. There is 3ft on each side of the car, which is more than most garages and parking spaces.

jccooper 3y ago

NFPA requirements for road tunnels is an emergency exit every 1000ft/300m. Cross-passages to another tunnel are acceptable, including a parallel travel tunnel if there's automatic traffic control. They may also be stairs or ramps. Secondary tunnels are not common; typically they are for long and/or deep tunnels. Dunno if the Vegas system would qualify as a road tunnel (thus NFPA 502) or some sort of transit tunnel, which might be a different thing. (I've not seen such exits provided in subway tunnels; emergency procedure seems to be "walk back to the station".) But in a short shallow system like in Vegas, they could have periodic cross-passages or stairs to the surface. Dunno if they do; never been in it.