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A dozen extra staircases wouldn’t have done much to save people in Grenfell tower. They were instructed to stay in place, because when building regulations are

A dozen extra staircases wouldn’t have done much to save people in Grenfell tower. They were instructed to stay in place, because when building regulations are followed, that’s the safest place to be. The problem with Grenfell was that building regulations had been violated, at which point, all bets about safety are off.

dpark 5y ago
I could see a layperson like me thinking “yeah, thick concrete and fire doors; you’ll never need to fully evacuate”. I would expect architects, fire marshals, city planners, and other experts to see the obvious problem with this. Or at least one of them. It’a a single building. How do you build a plan around never needing to evacuate the place? It seems straightforward and appropriate to support a full evacuation strategy. Is “stay in your flat while the building burns down around you” a common fire safety plan in the UK? Because that seems scary as hell. And also negligent.
- afirement 5y ago
  Apartment doors, walls and floors can withstand many hours of continuous burn. The building would never be on fire, at worst you’d have one apartment or one floors public areas on fire before it’s put out. If my apartment was on fire, no alarms would sound in the building, only within my apartment, it doesn’t matter to my neighbours. There’s certainly scenarios in which you might need to evacuate, like a bomb threat, but we are speaking about internal fire, in which case there’s more danger in hundreds of people fleeing in panic down stairs (whether that’s 1 stair case or 2) than staying inside.
  - dpark 5y ago
    > there’s more danger in hundreds of people fleeing in panic down stairs (whether that’s 1 stair case or 2) than staying inside. Is there? I’ve never seen people panic when a fire alarm goes off. Maybe if the fire alarm is going off as the building is filling with deadly smoke people would panic. But then that seems appropriate (or at least better than sitting and waiting to die of smoke inhalation). Pretty sure the Grenfell situation would have ended better by having everyone evacuate. And yes, the incompetent cladding work makes that a special case. But a huge amount of our codes are for a special case. Every so often it saves 70 lives.
    - sofixa 5y ago
      The problem isn't only a potential panic. While the people are evacuating, how does the fire brigade get to where they need to combat the fire in the apartment?
      - dpark 5y ago
        This is sort of a comical response. The building is engulfed in flames and plan is to keep the stairwells clear. If the concrete and fire doors are doing their supposed job, then the fire brigade can just wait. If the concrete and fire doors are not doing their job, then getting people out is far more important than getting the fire brigade in.
        sofixa 5y ago
        > If the concrete and fire doors are doing their supposed job, then the fire brigade can just wait. Wait until the people in the apartment on fire die? (Either it starts in an apartment, or a common are which would block the escape of inhabitants living on there or higher)
        dpark 5y ago
        I’m struggling to understand the scenario you’re describing. So the alarm goes off because an apartment is on fire. In response to this, everyone else waits until the fire brigade shows up to attempt to exit? I’m pretty sure if people are going to evacuate, they’ll do this in response to the alarm, and not wait and block the stairs. Also I’m pretty sure the fire brigade can tell them to get the out of the way to get up the stairs if necessary. How narrow are these stairs anyway? And why did everyone not evacuate before the fire brigade showed up? I just find the “apartment on fire, but everyone is blocking the stairs so the fire brigade can’t get to the burning apartment” scenario to be far fetched. Are there documented cases of this? Because there is at least one documented case of people sheltering in place and the building burning around them.
  - chrisseaton 5y ago
    > Apartment doors, walls and floors can withstand many hours of continuous burn. 24 stories of Grenfell were engulfed in an hour - the fire bypassed the doors, walls and floors, by going up the outside. > The building would never be on fire The entire building was on fire. 72 people died. > The problem with Grenfell was that building regulations had been violated, at which point, all bets about safety are off. Mistakes get made. Hence redundancy, like two staircases. If you're going to design for 'no mistakes ever made' then don't bother with any fire systems as a fire is a mistake in the first place.
    - pas 5y ago
      The correct approach is to design for the biggest common mistakes, not for all mistakes ever. We already do this for floods, earthquakes, wind load, etc.
      - chrisseaton 5y ago
        This cladding was common. They’re still trying to remove it from buildings now.
        pas 5y ago
        Trying. Because the UK government absolutely does not give even a single fuck. Housing is a shitshow everywhere. (A symptom of completely bonkers politics in general.)
    - sofixa 5y ago
      > 24 stories of Grenfell were engulfed in an hour - the fire bypassed the doors, walls and floors, by going up the outside Because the exterior was flammable, which isn't the norm and is actually criminal.
      - chrisseaton 5y ago
        > is actually criminal So is arson. Newsflash: sometimes people do criminal things. But we try to design to cope with it rather than just saying ‘but they aren’t allowed to start that fire so no need to guard against it.’ And it turned out it was the norm, hence the huge panic to fix it in so many buildings.
  - michael1999 5y ago
    I never feared fire when living in a high rise, and never had to evacuate except for drills. But here’s a recent counter example where shelter-in-place can go wrong. https://www.thestar.com/news/2021/toronto-fire.html https://www.thestar.com/news/2021/toronto-fire.html
- cardiffspaceman 5y ago
  In 2001 when the Twin Towers came down, people were trying to desert the building. Is there an analysis that shows they would have been just as safe in their offices?
  - coryrc 5y ago
    Did the second staircase help?
    - bobthepanda 5y ago
      Actually, yes. (Well, the third one did.) The South Tower had one remaining stairwell survive impact and 18 people were actually able to evacuate from above the impact zone, which is actually pretty impressive when you consider that the impact was on floors 77-85, and the people who called emergency services were told to stay in place. One of the survivors was actually only 20 feet (6 m) from the left wing. https://en.wikipedia.org/wiki/Stanley_Praimnath https://en.wikipedia.org/wiki/Stanley_Praimnath That being said, a lot of fire codes and related legislation had to be updated in the wake of 9/11. Among the many other dumb things: * the stairwells were all extremely close to each other. In the North Tower they were 70 ft (21 m) apart and in the South Tower they were 200 ft (60 m) apart, which is probably why one stairwell survived in the South Tower and none did in the North. * stairwells were only surrounded by drywall instead of concrete, which is another contributing factor to why so many of them were rendered inoperable. If you're not familiar with drywall, you can literally punch a hole through it with your arm. * stairwells were built with a 44 inch width because it was assumed that the average person had a shoulder to shoulder width of 22 inches (55 cm). This slowed down evacuation a lot. * the fire code was incorrect. the building was only half full but took much longer to partially empty than a full evacuation of the full occupancy tower was projected to take. so codes were revised. * there were not enough stairwells according to code. but how might this be? well, the owner and constructor, the Port Authority of New York and New Jersey, is a federally created entity, and so is not actually subject to local fire codes. (This last point wasn't actually addressed; they're still not actually required to follow NYC fire codes, but they did at least do so for the new iteration of the towers.) * In a previous attack on the WTC, people were evacuated from the roof, but since that incident the roof doors were locked to prevent base jumpers from gaining access. https://www.history.com/news/world-trade-center-stairwell-design-9-11 https://www.history.com/news/world-trade-center-stairwell-de...
- PebblesRox 5y ago
  It does seem to be the norm for the UK: “In the United Kingdom... residential buildings are designed with a stay-in-place firefighting strategy as opposed to simultaneous evacuation, and regardless of building height, maximum occupancies determine staircase width, resulting in many tall buildings serviced by a single stair core. On June 14, 2017, one such building, the Grenfell tower, was engulfed by the deadliest residential fire in the United Kingdom since the Second World War and cost the lives of 72 people. Subsequent inquiry determined that the negligent use of combustible cladding and insulation caused the rapid spread of the fire up the building exterior. The tower consisted of a 24-storey concrete structure with a single central exit stair, for which the shelter-in-place evacuation policy was sustained for more than 80 minutes before a general evacuation was ordered.” https://secondegress.ca/A-Wicked-Problem https://secondegress.ca/A-Wicked-Problem

dpark 5y ago

I could see a layperson like me thinking “yeah, thick concrete and fire doors; you’ll never need to fully evacuate”. I would expect architects, fire marshals, city planners, and other experts to see the obvious problem with this. Or at least one of them. It’a a single building. How do you build a plan around never needing to evacuate the place? It seems straightforward and appropriate to support a full evacuation strategy. Is “stay in your flat while the building burns down around you” a common fire safety plan in the UK? Because that seems scary as hell. And also negligent.

afirement 5y ago
Apartment doors, walls and floors can withstand many hours of continuous burn. The building would never be on fire, at worst you’d have one apartment or one floors public areas on fire before it’s put out. If my apartment was on fire, no alarms would sound in the building, only within my apartment, it doesn’t matter to my neighbours. There’s certainly scenarios in which you might need to evacuate, like a bomb threat, but we are speaking about internal fire, in which case there’s more danger in hundreds of people fleeing in panic down stairs (whether that’s 1 stair case or 2) than staying inside.
- dpark 5y ago
  > there’s more danger in hundreds of people fleeing in panic down stairs (whether that’s 1 stair case or 2) than staying inside. Is there? I’ve never seen people panic when a fire alarm goes off. Maybe if the fire alarm is going off as the building is filling with deadly smoke people would panic. But then that seems appropriate (or at least better than sitting and waiting to die of smoke inhalation). Pretty sure the Grenfell situation would have ended better by having everyone evacuate. And yes, the incompetent cladding work makes that a special case. But a huge amount of our codes are for a special case. Every so often it saves 70 lives.
  - sofixa 5y ago
    The problem isn't only a potential panic. While the people are evacuating, how does the fire brigade get to where they need to combat the fire in the apartment?
    - dpark 5y ago
      This is sort of a comical response. The building is engulfed in flames and plan is to keep the stairwells clear. If the concrete and fire doors are doing their supposed job, then the fire brigade can just wait. If the concrete and fire doors are not doing their job, then getting people out is far more important than getting the fire brigade in.
      - sofixa 5y ago
        > If the concrete and fire doors are doing their supposed job, then the fire brigade can just wait. Wait until the people in the apartment on fire die? (Either it starts in an apartment, or a common are which would block the escape of inhabitants living on there or higher)
        dpark 5y ago
        I’m struggling to understand the scenario you’re describing. So the alarm goes off because an apartment is on fire. In response to this, everyone else waits until the fire brigade shows up to attempt to exit? I’m pretty sure if people are going to evacuate, they’ll do this in response to the alarm, and not wait and block the stairs. Also I’m pretty sure the fire brigade can tell them to get the out of the way to get up the stairs if necessary. How narrow are these stairs anyway? And why did everyone not evacuate before the fire brigade showed up? I just find the “apartment on fire, but everyone is blocking the stairs so the fire brigade can’t get to the burning apartment” scenario to be far fetched. Are there documented cases of this? Because there is at least one documented case of people sheltering in place and the building burning around them.
- chrisseaton 5y ago
  > Apartment doors, walls and floors can withstand many hours of continuous burn. 24 stories of Grenfell were engulfed in an hour - the fire bypassed the doors, walls and floors, by going up the outside. > The building would never be on fire The entire building was on fire. 72 people died. > The problem with Grenfell was that building regulations had been violated, at which point, all bets about safety are off. Mistakes get made. Hence redundancy, like two staircases. If you're going to design for 'no mistakes ever made' then don't bother with any fire systems as a fire is a mistake in the first place.
  - pas 5y ago
    The correct approach is to design for the biggest common mistakes, not for all mistakes ever. We already do this for floods, earthquakes, wind load, etc.
    - chrisseaton 5y ago
      This cladding was common. They’re still trying to remove it from buildings now.
      - pas 5y ago
        Trying. Because the UK government absolutely does not give even a single fuck. Housing is a shitshow everywhere. (A symptom of completely bonkers politics in general.)
  - sofixa 5y ago
    > 24 stories of Grenfell were engulfed in an hour - the fire bypassed the doors, walls and floors, by going up the outside Because the exterior was flammable, which isn't the norm and is actually criminal.
    - chrisseaton 5y ago
      > is actually criminal So is arson. Newsflash: sometimes people do criminal things. But we try to design to cope with it rather than just saying ‘but they aren’t allowed to start that fire so no need to guard against it.’ And it turned out it was the norm, hence the huge panic to fix it in so many buildings.
- michael1999 5y ago
  I never feared fire when living in a high rise, and never had to evacuate except for drills. But here’s a recent counter example where shelter-in-place can go wrong. https://www.thestar.com/news/2021/toronto-fire.html https://www.thestar.com/news/2021/toronto-fire.html
cardiffspaceman 5y ago
In 2001 when the Twin Towers came down, people were trying to desert the building. Is there an analysis that shows they would have been just as safe in their offices?
- coryrc 5y ago
  Did the second staircase help?
  - bobthepanda 5y ago
    Actually, yes. (Well, the third one did.) The South Tower had one remaining stairwell survive impact and 18 people were actually able to evacuate from above the impact zone, which is actually pretty impressive when you consider that the impact was on floors 77-85, and the people who called emergency services were told to stay in place. One of the survivors was actually only 20 feet (6 m) from the left wing. https://en.wikipedia.org/wiki/Stanley_Praimnath https://en.wikipedia.org/wiki/Stanley_Praimnath That being said, a lot of fire codes and related legislation had to be updated in the wake of 9/11. Among the many other dumb things: * the stairwells were all extremely close to each other. In the North Tower they were 70 ft (21 m) apart and in the South Tower they were 200 ft (60 m) apart, which is probably why one stairwell survived in the South Tower and none did in the North. * stairwells were only surrounded by drywall instead of concrete, which is another contributing factor to why so many of them were rendered inoperable. If you're not familiar with drywall, you can literally punch a hole through it with your arm. * stairwells were built with a 44 inch width because it was assumed that the average person had a shoulder to shoulder width of 22 inches (55 cm). This slowed down evacuation a lot. * the fire code was incorrect. the building was only half full but took much longer to partially empty than a full evacuation of the full occupancy tower was projected to take. so codes were revised. * there were not enough stairwells according to code. but how might this be? well, the owner and constructor, the Port Authority of New York and New Jersey, is a federally created entity, and so is not actually subject to local fire codes. (This last point wasn't actually addressed; they're still not actually required to follow NYC fire codes, but they did at least do so for the new iteration of the towers.) * In a previous attack on the WTC, people were evacuated from the roof, but since that incident the roof doors were locked to prevent base jumpers from gaining access. https://www.history.com/news/world-trade-center-stairwell-design-9-11 https://www.history.com/news/world-trade-center-stairwell-de...
PebblesRox 5y ago
It does seem to be the norm for the UK: “In the United Kingdom... residential buildings are designed with a stay-in-place firefighting strategy as opposed to simultaneous evacuation, and regardless of building height, maximum occupancies determine staircase width, resulting in many tall buildings serviced by a single stair core. On June 14, 2017, one such building, the Grenfell tower, was engulfed by the deadliest residential fire in the United Kingdom since the Second World War and cost the lives of 72 people. Subsequent inquiry determined that the negligent use of combustible cladding and insulation caused the rapid spread of the fire up the building exterior. The tower consisted of a 24-storey concrete structure with a single central exit stair, for which the shelter-in-place evacuation policy was sustained for more than 80 minutes before a general evacuation was ordered.” https://secondegress.ca/A-Wicked-Problem https://secondegress.ca/A-Wicked-Problem