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Comment by zkms | Hacker News Reader

> It seems to me that the biggest issue with the fire system was the lack of a graphical display of the alarm

i agree that the lack of a graphic/synoptic display for the smoke detection system was a horrid flaw, especially when rapid response is needed.

However, i feel that the lack of an automatic extinguishing system was pretty grave too; given the excellent record of automatic fire sprinklers in containing -- if not fully extinguishing -- fires, well before the fire brigade arrives.

Of course, accidental activation is a serious concern, but this can be addressed, whether through the use of a double-interlock preaction scheme (where the piping is kept water-free with a valve that is opened only when the heat/smoke detectors signal a fire; and even once the pipes are filled with water, sprinkler heads need to be individually activated with heat) or using a gaseous clean-agent instead of water.

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I've written a touch panel UI for a next-gen sprinkler system. The valves themselves used high-pressure mist to bind smoke particles and minimize liquid damage often associated with sprinklers, and could be individually shut off when needed. I think the rationale was that by minimizing collateral damage you could install sprinklers in places where they would be considered a liability.

I heard the largest end customers were shipbuilders and police stations; a few systems were installed in underground public spaces such as train stations.

(Don't ask if the police has ever used the water spray as a taming device in the cells. I don't really want to know.)

I doubt it would work. How is dealing with slippery wet angry prisoners an advantage over dry angry ones?

Totally off-topic, but this reminds me of a story from a psychiatric nurse I know. They apparently once had to deal with someone who decided to strip down, then cover themselves head to toe with some form of body oil they'd managed to get hold of. Hilarity ensued.

Honestly, oil and hilarity aren't too bad, all told. I've heard stories of prisoners and mental patients using blood, or poo.

I imagine the severity of the hilarity was dependent on whether or not one's job description implicitly included "preventing patients from using the corridor as an otter slide".

There are many accounts of police abusing people for apparently purely sadistic reasons. Their behavior is not always rational.

Water dries eventually.

First a disclaimer: I’m probably misinterpreting you, so I apologize in advance. I sincerely assume you have only the best intentions.

By my interpretation, your last paragraph seems to accuse police of very specific misbehavior, but without any evidence, and even with an explicit desire to avoid resolving your accusation one way or another.

I hope you agree that we should take every single accusation of wrongdoing extremely seriously: only then can we truly achieve accountability for bad behavior, while celebrating and rewarding good behavior.

Unfortunately, purely speculative accusations of specific wrongdoing like this compromises our ability in general to take accusations seriously! It also subtly harms the reputations of good people within the accused group, if the accusation is unfounded.

For example, imagine if I said out of the blue:

“I worked with <anilakar> through all April 2019. (Don’t ask me if <anilakar> ever stole a MacBook Pro from the Apple Store on April 5th 2019 at 3:45pm. I don’t want to know anything about whether that did or did not happen.)”

Hopefully this illustrates the potential harm of such comments.

If anilakar had a reputation for abusing their authority, then such a comment would not necessarily be out of place. Possibly rude and unneeded, but not out of place. Police as an organization routinely abuse their authority. I've personally suffered such behavior in jail.

anilakar worded their comment such a specific fashion as to avoid making any accusations. They are allowed to muse openly. Your comment is unnecessary.

> there was also a conservative approach to preserving the historic wooden structure in its unadulterated form. The designers were determined not to alter the attic with protective measures like sprinklers or fire walls.

> A willingness to sacrifice its pristine state for a compromise between what was possible 850 years ago and what is sensible today could have saved the spire, experts said...

> But the main reason to opt against fire walls, Mr. Mouton said, was because it risked “mutilating” the structure. “It’s true,” he said, that the idea had been floated at the time, “but it was discarded.”

> “It changes the appearance but also the elements, because to put up a partition you need to cut the wood. It’s mutilating,” Mr. Mouton said. Mr. Prunet added that sprinklers were not added because they would “drown the whole structure.” Instead, they said, the team had banked on prevention and detection. This was a conscious choice.

https://www.nytimes.com/2019/04/19/world/europe/notre-dame-f...

> Mr. Prunet added that sprinklers were not added because they would “drown the whole structure.”

Waiting for the fire department to show up and start spraying the structure with high-pressure hoses in order to contain a fire that got much larger in the intervening time because it wasn't being mitigated by a sprinkler system, on the other hand, doesn't seem to have damaged the structure at all.

Hindsight really is 20/20.

It's also interesting that fire mitigation measures were discarded in the interest of historic preservation. The charpente being a part of the building that basically nobody ever sees, the question arises, "preserving it for who?" Or had the preservation become an end in and of itself?

And the roof was not part of the original structure, it had been completely rebuilt, yes a long time ago, but still completely rebuilt. My guess is that if they had access to modern materials at the time, they would have opted for that.

Also, the tall spire was added (historically) fairly recently. It was not an original part of the roof that burned. So apparently, earlier people were not "afraid" of altering it.

That was a bonus in addition to the restauration works that took place mid-19th century.

> drown the whole structure

My house has a fire sprinkler system. Each nozzle is heat activated, in that the heat from a fire melts a plug allowing the water to flow. Only the hot valves activate, not everything.

The contractor told me which would I prefer, a sprinkler spraying some water around, or a firehose through the window?

I don’t think that’s really contradictory though. I’ve lived through many cases of the sprinklers being set off accidentally (frozen pipe burst, rc-helicopter blade impact, and idiots using it as a clothes hook) and “some water” isn’t the phrase I would use. I think it’s more like if someone threw a bathtub from the ceiling every minute until someone could shut it off? That can be pretty costly to mitigate afterwards—but then I’ve also seen houses where nothing of it could be saved. As your contractor said, one of those is probably much better.

Mine are flush with the ceiling, there's nothing to hook onto. Just regular plumbing pipes can freeze, too. But the sprinkler pipes all run in interior walls - it's the ones in exterior walls that are likely to freeze. (I've had floods from frozen pipes in a non-sprinkled house - the pipes were in an exterior wall.)

Anyhow, at the time I did some research and found that nobody had died in a fire in the US in a room that had working sprinklers. It's pretty darn compelling.

> I’ve lived through many cases of the sprinklers being set off accidentally (frozen pipe burst, rc-helicopter blade impact, and idiots using it as a clothes hook) and “some water” isn’t the phrase I would use. I think it’s more like if someone threw a bathtub from the ceiling every minute until someone could shut it off?

That's why i specifically mentioned double-interlock preaction systems, where if someone hits the sprinkler and causes it to open, the only thing that comes out is compressed air (and a trouble/supervisory alarm sounds).

> However, i feel that the lack of an automatic extinguishing system was pretty grave too

Or perhaps wrapping or covering the wood in mineral/stone wool insulation:

* https://www.youtube.com/watch?v=Bc_nPWMEdgs

* https://www.youtube.com/watch?v=KgO7zw7NWLc

Rockwool is the most popular product, so you'll see a lot of videos (like above) featuring them, but I'm sure there are others.

Of course an extinguisher system can also be added, but a bunch of batts could be done quickly and inexpensively for a quick win.

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