Because the existing safety mechanisms are vastly more effective, perhaps?
You might need them only to prevent deaths by humans falling without the cart, which the buffers won’t save anyway. Come to think of it, if there is a chance of humans being impaled on the buffer it might be more worthwhile to install a naked human mattress instead of a buffer since the buffer would be so rarely needed compared to the mattress used due to the multiple other safety mechanisms.
Now whether such a device would be fittable and useful in an elevator shaft I do not know. Especially since it would have to be removed every time you’re doing mantenance on the shaft bottom.
It takes about 7 seconds to free fall 84 stories. The description from the passengers SEEMS to describe a longer descent (people praying, etc). Did any of the passenger’s reports indicate that people or objects were floating around the elevator, as would happen in free fall?
Right click on the link and choose to open the window in “incognito” or “private” mode. You will get ads, but most media sites will open this way. Also, many will have a counter that allows a certain number of articles per month; generally it’s between three and ten. Simply delete the cookie, and the counter re-sets for most of these sites. The smallest sub-set also has ad-blocker detection, and will block you until you “whitelist” the site to view ads. This is part of the contract they make with their advertisers, so should not be circumvented.
Those mattresses are huge precisely because they dissipate the force horizontally. There isn’t enough space in most high rises, even if you took up the whole first floor. For high-speed cars, harm reduction is still possible using a combination of springs and oil hydraulics though.
These systems also serve to protect any workers caught in the elevator well during an emergency. You will see a line marked on the buffer indicating the height below which one must duck.
Elevator buffer test.
Warning: F-bombs ahead. Mute recommended.
Mainly they are not needed. I have only heard two elevators free falling. Empire State Building when the ropes were cut by a bomber crashing into the building, the World Trade Center. The cushions would have made no difference in this case. The elevator stopped on the 11 the floor. And as I said earlier I doubt that it was free falling.
Air resistance can also be significant in an elevator, since the air can’t quickly escape the shaft. Which means that even in a situation with all cables cut and no emergency equipment working, you’re not going to get much of things floating around in the car.
Are those safeties as reliable as the ones that let the car fall 83 stories?
Maybe, maybe not. But it doesn’t matter. Elevators (like most potentially-dangerous engineering feats) have multiple independent safety systems, each of which fails only very rarely. If you have four different safety systems, and each has a 99% success rate, then you’ll only actually have a failure one time in a hundred million.
The articles all say “plunge” or “fall” but we really have no information about how fast is actually “fell.” No cite provided, but I read on another site that the “clack clack clack” heard may have been the emergency system lowering the elevator to the bottom where the door could be opened (since it’s express). Really, we don’t have any information about what actually happened and there hasn’t been any update to the story since it happened.
1st I doubt the elevator fell. It probably motored down 83 stories. And if the car had come close to reaching the end of shaft the safeties would have shut down the MG set and the motor and applied the brake.
So yes they are reliable with multiply levels of operation.
If you are ridding an elevator and there is a failure and the 1st level of safety is operation I probably won’t notice unless I am paying attention, you will not have any idea. 2nd level I will detect something wrong. 3rd level you might notice it is not operating smoothly if you are paying attention. 4th You will begin to wonder. 5th the elevator will stop badly at the floor. 6th the elevator will just stop now. And behind all this there are still the end of run safety stop, then the end of shaft stop. Pluss many mechanical fail safes.
That would make sense. With a cable loose in the shaft getting tangled in God knows what if it was trying to go down on inspection speed you could get that kind of noise.
Sure.
Land is VERY expensive in downtown Chicago and parking structures of multiple stories common. The building has a couple levels retail space at street level, then the parking levels. Residential levels start at, I think, floor 44.
I used to know someone who lived in Marina Towers, another (if smaller) high rise. The first 19 floors of those buildings were parking lot, with the residences above that. The building formerly known as John Hancock probably has a lot more than that, what with being a larger/taller building and all.
I believe that reports from national/aggregator sites were sensationalistic
I *strongly *suspect that the folks here – like bob++, enalzi, and Snnipe 70E – are correct to doubt that the elevator “plunged” down those 84 floors. The descent was likely much slower than the headlines suggest.
While I’m limited to the same news reports as everyone else, let me offer the following observation on coverage of the incident: I live in Chicago, and this news story made the rounds here for a day or two before I started seeing it show up on national news aggregator sites. I did not see language like “plunge” or “plummet” in the local newspapers. Those descriptors come from non-local outfits who were rewriting the rewrites that other sites rewrote. Like a big ol’ game of telephone.
Perhaps, you might say, the local press treated the incident with kid gloves. Maybe, but I don’t think so. This ain’t that kind of town.
could be in a service hallway or closet which wouldn’t have the same finish as the rest of the floor.
One more note, I don’t see anything that shows that the “drop” actually started on the 95th floor. The 84 number is just based on the fact that they got on at the 95th floor. It’s been years since I’ve been on it, but the elevator is already extremely fast and being express I don’t think it shows what floor you’re on.
Unfortunately, journalists and editors tried to convince food shops and mortgage companies of the benefits of giving away their products for free too, but it didn’t work out.
Thanks for the tips.
Nobody’s asking newspapers to give away their product for free. The objection is that they’re charging their product for the privilege of being their product.
You are not a newspaper’s customer.