The WTC (like all modern high-rises in the developed world) had a pretty impressive set of firefighting and evacuation infrastructure, procedures, and personnel. This training video goes through it pretty well [0].
- Smoke detectors and pull stations everywhere to ensure any fire is detected and responded to quickly (i.e. before it gets out of hand). There was a fire station across the street.
- A huge console for responding firefighters to see the location of alarm conditions, make building or floor-wide announcements, and even have two-way conversations with intercom stations on particular floors.
- Sprinklers and redundant power for the pumps that run them.
- Fans to push smoke out of the building and supply clean air to evacuation routes.
- Fire stairs, kept closed under positive pressure to keep smoke out, kept unobstructed by regular patrols, encased in material that wouldn't burn through for hours.
- A network of piping and wall-mounted hoses easily fed from the dedicated fire-truck parking.
- Fire drills, designated authorities for the evacuation of each floor, security personnel trained to watch over the fire alarm equipment.
It's not like the WTC wasn't prepared to evacuate in a fire. It's just that nobody anticipated all that infrastructure (pipes, stairwells, etc) getting sheared through by an airplane.
Fire stairs, like, a single column of stairs, or, multiple columns? If they were placed near each corner, some of them should have survived until collapse.
Impact by planes had been imagined prior to the crashes, but I don't know if it had been by the designers. Considering these were very tall structures, it seems likely someone would have at least briefly imagined it.
There were 3 stairwells in each building. Here's an excerpt from this fascinating wikipedia page[1] about one of the only four people to make it out from above the impact in the South tower:
"The airliner that struck the North Tower struck it perpendicular to the north face. The impact severed all the elevators and all three stairwells. The airliner that struck the South Tower struck at an angle, severing two stairwells, but it left Stairway A, the one they were using, more or less intact."
At some point you have to make an ethical decision -- what is the best allocation of society's resources? It would be expensive to outfit all tall buildings with parachutes in the exceedingly unlikely event that they would be useful -- and that's before you factor in the low probability that they would successfully save people with little to no training in normal parachuting, much less BASE jumping, a sport which often kills trained participants jumping under far more favorable conditions.
You might as well ask why people who work in tall buildings don't take parachutes to work themselves. The answer is obvious, and I hope it's equally obvious why buildings don't do this.
On a related note: having to send your shoes through the x-ray machine in an airport security line is almost as bad of an idea. :/
> why wouldn't I want one if my only choice were to splat or char?
That isn't your only choice because the scenario is exceedingly unlikely to happen.
If safety is your thing, you'd be much better off spending the several thousand dollars on doctors visits, healthier food, gym memberships, and/or public transit throughout the year.
It's unlikely a seatbelt will save my life, but every car I go in has multiple.
The original argument presented here is equivalent to arguing it's too expensive and useless to carry enough lifeboat capacity for everyone on a ship after the Titanic sunk. It's extremely unlikely that I'll ever impact an iceberg.
How many times do you practice putting on your seatbelt, and how long does it take to put it on? For me, I put on my seatbelt every time I enter a car, and it takes me seconds.
I've never put on a parachute or practiced deploying one.
Lifeboats are not just for iceberg collisions. There are many reasons for a boat to sink that don't involve a collision.
Practically no one had put on a seat belt before they were introduced either. The cost of parachutes and placards to describe their proper usage is absolutely trivial in consideration of the budget of any building from which parachutes could actually be deployed.
Buildings don't just collapse from airplane collisions; fires, bombs, earthquakes, structural failure, hostile takeover, and more could all be scenarios where you might only survive if you have a chute.
How many people have died in building collapses over the last 50 years? Alternatively, how many people have died in car crashes? Large boats getting sunk? Lightning strikes?
Obviously these are rhetorical questions: it is far, far more likely to be hit by lightning than to die in a building collapse.
If you truly believe this risk is worth mitigating I would put my money/time where my mouth is and not depend on some building supervisor to keep enough parachutes around and keep them in good condition. Instead you should get some training*, buy a BASE jumping parachute and take it with you when you go above 60m. As you say, they are relatively inexpensive.
[1] Note: be careful -- you are much more likely to be killed in your training than you are to need to use it.
That's about the first sensible thing I've seen you say in this thread.
Yes: it's far more cost effective to avoid the risk altogether than attempt to mitigate the exceptionally unlikely event of a very-tall-building collapse or fire, particularly through use of, say, parachutes (into an urban landscape with many landing hazards and few readily accessible landing zones).
On the other hand, that decision also means foregoing opportunities, including the income potential of working for a firm in or near a dense downtown with such tall office towers in it. A cost you might be willing to accept.
Risks and costs can be balanced, though the cases in which people make decisions which are both fully informed and rational strike me as relatively rare.
The supply of highly suspended office space is quite limited and I'd guess that almost none of the highest paid workers work in one. If the cost of a few dozen parachutes is deemed too expensive to hold in reserve for emergencies then I have to seriously doubt that such a space could have much real-increase on income. At best, I'd expect the ownership to collect much of the increase in rent as the small supply is fought for.
I'm sorry, would you care to answer the question of how many times you've put on a seatbelt versus how many times you've BASE jumped? For me, that ratio is whatever 50000 divided by zero is.
Cost of installation is by no means the only factor or cost in making a safety feature. In another comment, you appeal to the many number of paratroopers who have jumped out of planes as prof that it can be cost-effectively, as if the cost of a paratrooper's jump could be reduced to the cost of a parachute.
I don't 'practice' (that is, with no intention of immediate utility) putting seat belts on. On the occasions I do put them on, it takes some small number of seconds to put on, depending on how complicated the system is and how accessible the various parts are.
Even if it took someone several minutes to strap on a backpack-like device, it would likely save lives in many scenarios.
As to my appeal to the cost of paratroopers' parachutes, that was in direct response to a very specific claim in the post I responded it to:
>It would be expensive to outfit all tall buildings with parachutes
30 meters doesn't seem all that useful. What is that - 9 floors? I guess it'd be better than nothing, but have there been a lot of preventable deaths in 10 story building fires where this would have saved them?
" and there were no plans for helicopter rescues from the roof, as the NYPD deemed it too unsafe to attempt due to dense clouds of smoke and rooftop antennas."
That said, I suspect that had they known the towers were going to go down within 2 hours, there might have been some different decisions made. But that's just hindsight. :/
Right it has been so long that I forgot it was a surprise that the towers collapsed that day. I remembered it a as being obvious, which it is in hindsight.
I'm guessing the tremendous amount of smoke and all the obstructions on the roof would have made this impractical. The situation wouldn't have been aided by helicopters falling on to rescuers below.
