Smoke detector sounders vs. control panel announcement

I

Ira

Active Member
Probably should have asked this before placing an order for a bunch of smokes...
 
Assuming a setup consisting of System Sensor 4-wire smokes daisy chained to an M1G, what are the pro's/con's of using smokes with internal sounders vs. smokes without internal sounders (and letting the M1G do the FA announcement over its speakers)? Not concerned with cost or installation benefits. Also, assume that there is a speaker in every location that has a smoke. Speakers connected via an M1TWA. This will be the only fire detection/alarm system in the home.
 
In case it matters... from a code standpoint, I live in a rural, incorporated village in Texas. When the home was built 20+ years ago, the only governmental agency inspections were State Windstorm (framing, roof, etc.), County water well and septic system, and State Flood Insurance (floor elevation). There were no electrical, mechanical, plumbing, etc. inspections. Same holds true today.
 
For people using smokes with internal sounders connected to a control panel with FA announcement via its speakers... do you disable some/all of the panel's speakers for FA announcements, or do you allow everything to "sound"?
 
I'm going to shudder a little when you state no inspections....
 
Think about what you are asking in regards to fire alarm....
 
In a fire alarm, you want there to be enough volume to wake a sleeping person to leave the premises, period. I believe that a smoke detector's sounder is appropriate and if you want to put an announcement to help with the evac, so be it, but I think the primary notification should be the device's integral sounder and tandem ring, then if you want the voice on top, so be it.
 
I would not depend on the voice and voice alone, same goes with system speakers. In the specific case of a residential fire alarm, the speaker circuits aren't usually supervised (and many not installed using fire rated cabling) so the edge goes to smoke detector as the means of notification. If a speaker fails or there's a wiring fault...let's be honest, the M1 isn't going to know unless it's an open circuit....and it's not required to nor should it have to.
 
In 99% of the M1's I've installed, I've yet to see a case where I needed to provide a speaker in every location for system notification purposes, but I can't comment to your design criteria. Remember, once you use a component to annunciate life safety conditions it's design considerations change.
 
We're enforced to be at least 80 dB at pillow height in any sleeping area by the ahj's in my locale, but the guideline is 5 dB above the maximum ambient or 75 dB at pillow height
 
I would recommend you read the cpsc document regarding the audibility of residential smoke alarms. It's a real eye opener and the numbers don't lie.
 
I thought about the lack of supervision on the "speaker path" being an issue after I made the OP, but I decided to let the question ride.
 
So what is the preferred approach for a FA event when some speakers are in [very] close proximity to smokes w/ sounders? Turn off the speakers during the entire FA event? Let speakers and sounders both sound during the entire FA event, and hope they don't cause confusion since the speakers and sounders won't be "in sync"? Turn off the speakers until the smoke sounders  for the FA event have been acknowledged/silenced, then put out a supplementary, explanatory message on the speakers until the system has been reset (assuming that's even possible to do)?
 
Thanks,
Ira
 
I know the HAI panel will silence interior sounders during a voice announcement, and then start them again after the voice is done... does the Elk do something similar?
 
You could use the sounders in the smokes as "interior sounders" for the noise, have them stop during the voice portion, and pick back up again.  Of course, you would have to figure out how to stop the sounders in the first place since it's probably polarity reversal triggered, right?
 
I wouldn't put system sounders in all the same locations as the system smoke detectors personally. With an M1 in some very large installs, I've yet to have an install where I really needed that many speakers installed....not to mention the additional considerations for impedance and amplification. Maybe a design consideration needs to be looked at further in your case? Maybe you need something like a M1 TWA to control the speakers...but that still doesn't address whether or not they're announcing and what they're announcing. I think it's going to be far more problematic to implement.
 
The smoke sounders should not silence nor be controllable from any other means then a fire alarm (on) and fire alarm reset (off). They need to maintain the temp-3 signaling and attempting to get them to do anything else is going to be very problematic....we're not talking about a programmable voice evac system (that costs 10-30X the amount of an M1 itself).
 
The speakers, if you're doing something like one per floor...there's going to be echo and slight delay between them. If you're looking at like 4-8 of them, I'd consider the install criteria itself. Probably not enough power on the M1 to effectively draw them and really be compliant for dB. Fire alarm is something that needs to be done by the book and meet the minimum for code and exceeding is far better.
 
@ Neil,
The OP is attempting to drive a compliant install, which means the smokes should have sounders and meet the dB rating in addition to tandem ring. The installation of system speakers is complicating the issue. The sound issue is going to be whether or not the OP wants to drive an evac event and annunciate just through the smokes and then with supplemental voice. The M1 does mute the siren sound when it's voice is announcing, but the smoke detectors will be driven in temp-3 by the reversing relay, so those will constantly be ringing in pattern when the panel is in alarm.
 
I think sight is being lost of why the fire alarm is there to begin with...wake people up and get them out of the house over the granular abilities of what can be done with the panel. While certain things can be done, it raises the questions and issues of should it be done...in the case of fire alarm, KISS is best.
 
DELInstallations said:
1. The smoke sounders should not silence nor be controllable from any other means then a fire alarm (on) and fire alarm reset (off). They need to maintain the temp-3 signaling and attempting to get them to do anything else is going to be very problematic....we're not talking about a programmable voice evac system (that costs 10-30X the amount of an M1 itself).
 
2. The speakers, if you're doing something like one per floor...there's going to be echo and slight delay between them. If you're looking at like 4-8 of them, I'd consider the install criteria itself. Probably not enough power on the M1 to effectively draw them and really be compliant for dB. Fire alarm is something that needs to be done by the book and meet the minimum for code and exceeding is far better.
Click to expand...
 
In regards to 1 above that is not how a FACP/System works.  A system does not have to be reset to silence the sounders and you would not want that. One of the first things a FD does on arrival is silence the system (so they can communicate) and look for the detector in alarm (if its not obvious).  If they had to reset the system they would lose the detector in alarm annunciation (LED on the head lit).
 
Regarding Item 2 in a Residential System it is not required to have the sounders in synch.  While it is advantageous to have synchronization so you can distinguish a temporal from a CO from a Burg alarm easier having one sounder per floor you should be able to unless there is something seriously wrong (an opinion).
 
also regarding the statement that the smoke detectors should have sounders to be compliant is false as far as NFPA and UL.  Smoke detectors (not smoke alarms) are not required to have sounders period or the NFPA and UL would not permit them.  It is just an easy way for an AHJ to "assume" the install meets the audiability requirements if the detectors have sounders (an opinion).  Proper sounders placed correctly can achieve the same results and meet the code.  Most AHJ's dont even have a sound meter that I have seen so they can and do specify that smoke detectors have sounders so they dont have to measure or they mix up the requirements between smoke detectors and smoke alarms (an opinion).  Smoke "alarms" such as noted in the CPSC document are required to have sounders.
 
In addition the voice output of the ELK-M1G is a supplemental output not evaluated by UL for evacuation purposes as it is not supervised as noted above.  The panel does have a voltage driven output for sirens that is supervised and should be used for evacuation purposes.
 
What you want to avoid is confusion in an emergency (an opinion).  Del is correct keep it simple (an opinion).  You dont want people slowing down to listen to a voice announcement (an opinion).
 
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