Miami Beach, Champlain Towers South apartment building collapse, Part 17 14

[SFCharlie]

A continuation of our discussion of this failure. Best to read the other threads first to avoid rehashing things already discussed.
Miami Beach, Champlain Towers South apartment building collapse
Miami Beach, Champlain Towers South apartment building collapse, Part 02
Miami Beach, Champlain Towers South apartment building collapse, Part 03
Miami Beach, Champlain Towers South apartment building collapse, Part 04
Miami Beach, Champlain Towers South apartment building collapse, Part 05
Miami Beach, Champlain Towers South apartment building collapse, Part 06
Miami Beach, Champlain Towers South apartment building collapse, Part 07
Miami Beach, Champlain Towers South apartment building collapse, Part 08
Miami Beach, Champlain Towers South apartment building collapse, Part 09
Miami Beach, Champlain Towers South apartment building collapse, Part 10
Miami Beach, Champlain Towers South apartment building collapse, Part 11
Miami Beach, Champlain Towers South apartment building collapse, Part 12
Miami Beach, Champlain Towers South apartment building collapse, Part 13
Miami Beach, Champlain Towers South apartment building collapse, Part 14
Miami Beach, Champlain Towers South apartment building collapse, Part 15
Miami Beach, Champlain Towers South apartment building collapse, Part 16


SF Charlie
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[Jeff Ostroff]

BraunEHC, where did this document come from? I had not seen it posted anywhere before

 

[FJBnomics]

Found this on Securitas settlement. With deepest pockets, the worse outcome of potential jury trial and nuclear verdict compelled their insurers to participate. They distanced themselves from liability and asserted they did not install or maintain security or safety systems, fire alarms or intercoms.

Clearly having the deepest pockets or largest Insurance Policy seems to be a 'negative' for companies in high profile litigation; especially with the LLC option. Quick and Easy to form a LLC, then put very little assets in the LLC, so less risk of loss. Perhaps LLC rents the office space and equipment from another LLC that the principles own. Thus for example, the structural PE limits his exposure and has a very limited less costly insurance policy to protect the LLC. Say a $16 Million Policy for an over 1 Billion Dollar Settlement. If LLC has to go belly up in process, and they just form another LLC and repeat the cycle.

I have an alarm question. Let’s assume there’s a properly designed alarm system in a 13 story residential building. I presume the system is intended to maintain building security and to keep residents safe in the event of a fire. How would we expect that properly designed and installed system to behave when the building collapses instead of catching fire or being broken into? I guess I am asking what normal system behavior would be.

Hopefully an expert will chime in, but my experience says if any Pull Station is manually pulled, the fire alarm should alert everybody in the building. Yes that is designed as a fire alarm, but that serves as great communication tool that there is an emergency in the building. I do not know how the Voice System worked, but I would think they have multiple ways to warn residents.

One being an automated response by Fire Alarm, like broken fire water line, Two being manual pull of any pull station in building, and third being the security person using the new voice system in all rooms. I would assume the voice system with stobes in each room, work on all forms of trip.

My take on supervisory event is perhaps, because of the false alarm in the lobby previously, they performed a supervisory event to say override the Lobby Pull Station setting off more than the lobby area alarms. I would expect that is a fire safety violation, but is bandaid to defeat false alarm problem in lobby?

Edit: Perhaps non emergency failure, like say one pull station or one strobe, thus that node is bypassed till fixed?

 

[Nukeman948]

...when the building collapses instead of catching fire or being broken into?
I guess I am asking what normal system behavior would be.

First of all, fire alarm and security systems will be two completely separate systems.

A security system may include cctv, card reader or keypad access, magnetically held or released security doors, hold up and panic buttons and any other security features the client may want.

A fire alarm system will have input devices like manual pull stations and automatic fire detection devices like smoke and/or heat detectors and sprinkler flow switches. The fire alarm control panel receives those inputs and determines the correct output based on its programing. Outputs would include things like audio/visual signals to alert occupants, call the fire department, send a signal to the elevator controller, release magnetically held fire doors and close fire dampers in air ducts.

If the building collapses those systems fail. Yes, that answer is a cop out, but even in a partial collapse, if the wiring shorts out and blows fuses in the control panel, it could render the whole system inoperable. We try to counter that issue by providing redundant circuit paths when possible but there are no guarantees.

So looking at what I believe happened at CTS, when the pool deck failed it broke some sprinkler pipes but the one flow switch for that floor was located in the north west corner of that floor so it still worked. It may have damaged the wires for the speakers at the east stairwell as the original drawings show the wires passed through the area that fell. If it was set up to sound the alarm for just that floor/zone*, those speakers may have failed because of the damaged wires, but the control panel was still able to call the monitoring company. All other floors had two flow switches, one in each stairwell, but when the main collapse happened it took out the fire pump and sprinkler supply so none of those flow switches had a chance to work.

*Often, alarms are set up to sound the alarm in one zone only for a set time period before sounding the alarm in the entire building unless the alarm is acknowledged at the panel to limit people becoming complacent from repeated alarms that don't affect them.

Speakers are used instead of horns when voice outputs are available and strobes are ADA compliant for hearing impaired but would not be required in an apartment unless needed on an individual basis.

Edit to add: A speaker system may give a horn sound for things like fires, a pre-recorded message could be played, or a microphone can be used to give details that are hard to program for in advance. But all of these speakers will be part of the fire alarm system.

[sub]Not an expert, but I did stay at a Holiday Inn once.
[/sub]​

 

[MJCronin]

NIST is pushing hard to meet their 2024 report completion date .....

MJCronin
Sr. Process Engineer

 

[SFCharlie]

This may have been posted while I wasn't looking...
NIST’s Investigations of Structural Disasters: What We Do and Why They Can Take Years to Complete
???


SF Charlie
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[Reverse_Bias]

The long investigation was never what bothered me. It's the fact that they are going to sit on all the evidence and findings until a conclusion is reached.

 

[MaudSTL]

@Nukeman948, thank you for your alarm system overview. That really helps my basic understanding. Naturally, I have another question. This one is about the typical nature of required human intervention.

In a multi-story residential building like CTS, does a fire alarm system typically rely on human intervention to activate recorded evacuation warnings? I can see from your description that the designer has to balance false alarms against catastrophic events. So I am imagining that in most cases they would expect a human to decide whether to evacuate the building and activate a switch to issue the recorded alert. If this is indeed the case, then that means that training an attendant like the security guard would be critical. And it also means that the attendant would be a weak link in executive function…for example, if the attendant were unable for some reason to activate the switch, then it would put all the residents at risk. If I am thinking about this correctly, would the system compensate for the attendant’s possible fallability with logic like, “If X happens and there is no human override within Y minutes, activate recorded evacuation announcement and strobes on all floors.”

 

[AusG]

From the NIST article:
"When a particular theory gains traction or popularity in the public, we may directly address it in our final report so that the public will understand why we did or did not believe that theory to be consistent with the available facts and evidence."
I'll be keeping an eye out for tar kettles

 

[BraunEHC]

Jeff Ostroff (Electrical)7 Jun 22 13:15
BraunEHC, where did this document come from? I had not seen it posted anywhere before

Found it on slipcase.com, here’s a link:
Link

 

[Nukeman948]

In a multi-story residential building like CTS, does a fire alarm system typically rely on human intervention to activate recorded evacuation warnings?

No. A fire alarm system would never be allowed that depended on human intervention to sound the alarm.
Recorded voice messages would be a customer option that is rarely used. They simply give a voice alarm instead of a blaring horn sound. The last one I installed used miniature cassette tapes and only gave a very basic announcements. Something like "May I have your attention please, A fire has been reported on your floor. Please exit the area immediately."...repeating for an eternity.

As soon as the control panel determines that a fire condition exists from inputs from things like smoke detectors, heat detectors or water flow switches, it will sound the alarms/strobes for the affected zone/floor (either recorded voice or horn sounds) and call the fire department or a monitoring company. After a set time period without acknowledgement from an attendant, a general alarm for the whole building will sound, but the alarm continues in the affected zone in either case. Time delays (with some limits) are used to limit false alarms, especially with flow switches. There are no silent alarms and the monitoring company would not be called without an evacuation announcement or horns/strobes for the affected zone.

The panel will remain in an alarm state until all input devices are cleared and reset. Water flow, smoke and heat detectors may be reset from the panel as long as water flow, smoke or heat are no longer present. Manual pull stations must be reset with a key or sometimes they will have a glass rod that breaks when it is pulled that must be replaced.

If equipped with a microphone, the attendant may select to make announcements to certain zones/floors or to the entire building. While announcements are being given the horns will be silenced and strobes will continue to flash. (It is possible that someone attempted to use the microphone and silenced the speakers but failed to make an announcement.)

Yes, the security company should have trained its people on how the fire alarm system operates and how to use the microphone to make announcements for any kind of emergency that may affect the residents.

[sub]
[/sub]​

 

[MaudSTL]

@Nukeman948, thank you so much for your clarification on how alarm systems typically handle human intervention. I actually feel much better to know that systems don’t typically function in the way I had imagined.

From the article posted earlier, so far we only know that someone activated the lobby pull switch. But there may be other human actions that have not yet been revealed.

I wish we could get that log. I wonder if it is possible to FOIA a copy. The Miami Herald did get to see it, according to a statement in one of their articles…but it is unclear if they actually have a copy of it.Maybe it will come up at tomorrow’s NIST meeting.

 

[SFCharlie]

Maybe it will come up at tomorrow’s NIST meeting.

I hadn't heard or seen anything on this?
Is there a video link?


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[SFCharlie]

National Construction Safety Team Advisory Committee Meeting
ncstac-june-8-9-2022-agenda-final-version (.pdf)
11:05 am – 11:45 am Champlain Towers South NCST Investigation Overview
11:45 am - 12:15 pm Champlain Towers South NCST Investigation Update
12:15 pm - 12:25 pm Committee Discussion of the Champlain Towers South NCST Investigation Update
12:35 pm - 12:40 pm Intro to Preliminary Collection and Analysis of Evidence
12:40 pm - 12:55 pm 3D Visualization of Evidence
12:55 pm - 1:10 pm Collection of Additional Evidence
1:10 pm - 1:25 pm Non-Destructive Testing of Evidence
1:25 pm - 1:40 pm Committee Discussion of Preliminary Collection and Analysis of Evidence
2:10 pm - 2:15 pm Intro to Invasive Testing of Evidence, Structural Testing and Analysis
(continued in next post)

 

[SFCharlie]

2:15 pm - 2:30 pm Invasive Testing of Evidence
2:30 pm - 2:45 pm Structural Testing
2:45 pm - 3:00 pm Computational Modeling and Analysis
3:00 pm - 3:05 pm Champlain Towers South NCST Investigation Concluding Remarks
3:05 pm - 3:25 pm Committee Discussion of Invasive Testing of Evidence, Structural Testing and Analysis

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[SFCharlie]

Did anyone register?

Anyone wishing to attend this meeting via web conference must register by 5:00 p.m. Eastern Time, Tuesday, May 31, 2022, to attend. Please submit your full name, the organization you represent (if applicable), email address, and phone number to Peter Gale at

Peter.Gale@nist.gov.

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[MaudSTL]

I will be present for the first half at least.

 

[SFCharlie]

The slides for the 2:45 "Modeling" look very interesting.
(the links in my schedule above, are for the slide .pdfs)

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[MaudSTL]

NIST has calibrated the video cam at 87 Park in order to enhance the collapse video in relation to their failure hypotheses.

>>>>Edit: I think we can give up any hope of seeing CCTV video from the CTS cameras. Note how this video slide refers only to home and commercial video sources.

>>>>>Edit: This entire process will extend to 2024-5, and NIST will not want to reveal much of anything until they publish. They plan to make 3D animations of their final hypotheses available at that time, but I don’t think we can look for anything sooner unless there’s a public outcry demanding something. I think this gives KCE the opening to provide an earlier hypothesis…assuming Surfside doesn’t terminate their agreement.

 

[Sym P. le]

The same insecurities as the NTSB? Is there a copy of the enhanced video available?

 

[MaudSTL]

Is there a copy of the enhanced video available?

Not so far.