[bigbubba]

> Worst case jumping from the 3-5th story is likely to result in serious injury but is often survivable.

A brief web search suggests to me that about 50% of people who fall from 15 meters (approx 4th floor) will die. Those are awful odds, and most survivers of falls from that height probably aren't landing on the sort of pavement you might expect to be surrounding a high-rise building. And how many of the survivers ever walk again? How many can even feed themselves again?

Seriously, 50% is worse than even russian roulette, a 'game' generally recognized as suicidal.

[Retric]

Again, it’s not how I would write these regulations. That said, regulators are working with real world data.

The expectation is for people to be able to exit the building or at least get to a lower floor, because that’s the usual case. Failing that ladders can generally evacuate people from the 5th floor. Jumping is very much considered a rare last resort, but is more controlled than people simply falling that distance. Further, first responders are more likely to be onsite which again increases the odds.

As an example of 4 people jumping from the 5th floor and only one being sent to the hospital. While everyone else in the building evacuated normally. https://www.independent.co.uk/news/world/europe/family-jumps...

So, while there are a lot of relevant regulations building height is a meaningful distinction.

PS: On an 18m tall building. The 1st floor is ~0 meters off the ground, the 2 floor is 3 meters up, 4th floor is ~12m up and 5th floor is thus 15m and the roof is at 18m. A window adds 1m but someone dangling removes ~2m based on their height. As in dangling from the 2nd story window is ~2m fall and a 15th floor balcony would be a 13m drop vs ~14m from a window. (Using G, 1, 2, 3, 4 is the same numbers just offset by 1.)

[bigbubba]

> The expectation is for people to be able to exit the building or at least get to a lower floor, because that’s the usual case.

That's the expectation in America surely, but is it in the UK? In America people are told to get the fuck out of buildings as fast as they can when the fire alarm goes off, but in the UK people are told to stay inside high rise buildings, apparently because they have fewer and narrower staircases. Highrise buildings in the UK are evidently not designed to be escapable. I think that should be the real scandal. The cladding is bad and effects hundreds of buildings, but how many UK highrise buildings have inadaquate stairways? Tens of thousands? More? The reason this isn't part of the scandal is probably because the scope of the problem is too enormous.

I encourage you to look up the timeline of events inside Grenfell; if evacuation began when the fire was called in, there would have been ample time for complete evacuation. 14 minutes elapsed between the initial call and fire spreading out the window of the origin flat. People were only reported trapped by smoke ~40 minutes after the fire was called in. These people were killed by the UK's policy of staying put inside buildings on fire.

Anyway, I've seen some videos of people falling a fraction of 15 meters onto pavement and dying. It seems depraved to expect somebody even on the third floor to jump onto pavement.

[Retric]

I don’t think the expectation is for this to happen frequently because it doesn’t, rather it’s part of the overall risk assessment. Total fire related deaths in the Great Britain is low and trending downward, trying to find jumping related deaths from the 3-5th floor is tough. https://www.statista.com/statistics/291135/fire-fatalities-i...

As to evacuations, that’s simply what happens in the overwhelming majority of cases. In England for the 12 months ending June 2020 there where 156,128 actual fires responded to and 231 deaths. https://assets.publishing.service.gov.uk/government/uploads/...

That’s with current regulations and resources. So, looking at that people are trying to balance spending more on fire safety vs very other issue and this is the balance they struck. I am not saying it’s perfect, just that it’s vastly more complicated than making every building as safe as possible with money as no object being the obvious correct choice. When you give that up then it’s all coming down to various compromises with different tradeoffs.

PS: Looking at the hard numbers, pushing evacuations might actually make things worse.

[bigbubba]

You have much more trust in UK authorities than I think they warrant. It is said regulations are written in blood; that means the regulations that preceded present regulations are the result of past experts being wrong. What are the chances that we are fortunate enough to live in a time when regulations are truly optimal and won't need to be changed in the future? Pretty low, I'd think. What are the odds that present regulations have been influenced and compromised by commercial interests? 100% guarantee, just look at the clusterfuck of an inquiry. If the government can't reclad a few hundred towers, do you think they'd dare condemn thousands of towers? They're addressing the cladding because it's feasible to fix, but retrofitting buildings with more stairwells? That's way more expensive, so it's being ignored.

There will be more fires, more deaths, and more changes to regulations. What experts say should be considered, but not treated as dogma. At best they are less wrong than their predecessors but more wrong than their future successors. If the people in that tower had disregarded the advice of extant UK experts, they would have gotten out alive. If that building had been constructed with more stairwells than UK experts presently say is required, they could have gotten out alive. If there had been an operational building wide alarm, as are found in American buildings, those people would have gotten out alive. There is a whole lot wrong with extant regulations in the UK, and commercial interests have politicians and the public ignoring most of it to focus on the cladding fraud (those responsible should be in prison for life, but the cladding fraud is not the only problem this fire revealed.)

> Looking at the hard numbers, pushing evacuations might actually make things worse.

This is not a crowded nightclub we're talking about; rapid evacuation of residential highrises is a reality in America. Please go look at the hard numbers of Grenfell, particularly the timeline of conditions inside the tower. There was ample time to evacuate the tower several times over. In modern America, most of the residents would have been waiting on the sidewalk before the firemen even got there. The building wide fire alarm would have been blasting their eardrums out.

[Retric]

Edit: I agree with almost everything you just said. But for clarification:

Not trust, just statistics. Great Britain has ~half the fire related deaths per million people vs the US. Various differences make comparing countries difficult, but their doing reasonably well vs the US.

Anyway, I don’t think the current system is optimal. However, fixing the stairwell issue before telling people to evacuate might be better than telling people to evacuate tomorrow. Eventually, evacuation is likely the better option and should therefore be the long term goal.

And so it goes across a million possibilities which is guaranteed to be suboptimal and interact with each other.

[Gibbon1]

Friend of mine was sitting on a balcony with three other people when the rotted joists gave way and they all fell 20 feet into the bushes below. The result was one lady with a skull fracture, a guy with broken ribs, and my friend with a compound fractured leg that involved his knee. He walks with a cane now.