Low Frequency Smoke Alarms

[AlexFullerton]

I don't need a study to show me that.

HAHAHA

 

[AlexFullerton]

Not sure you will be able to get around that or not. I'm not an expert, but it might be a lot simpler to just install on in R1 and R2 and be done with it. They aren't too expensive. Any reason why just one unit?

 

[Strathead]

I'm not sure I understand your dilemma. Are you trying to set off the horn/strobe only when the smoke alarm in that apartment goes off?

Depends on your system. Addressable Simplex, simply program it. Standard horn strobes will require a 24VDC constant power circuit that feeds through an addressable relay for each room that taps the 24VDC and those get programmed is one way I have done it.

 

[JoeStillman]

I'm not sure I understand your dilemma. Are you trying to set off the horn/strobe only when the smoke alarm in that apartment goes off?

Per IBC;

[F] 907.2.11.5 Interconnection

Where more than one smoke alarm is required to be installed within an individual dwelling unit or sleeping unit in Group R or I-1 occupancies, the smoke alarms shall be interconnected in such a manner that the activation of one alarm will activate all of the alarms in the individual unit. Physical interconnection of smoke alarms shall not be required where listed wireless alarms are installed and all alarms sound upon activation of one alarm. The alarm shall be clearly audible in all bedrooms over background noise levels with all intervening doors closed.

Our clients are used to using multiple station smoke alarms in apartments, but no smoke alarms meet the new 520 Hz rule. We're trying to figure out what the least expensive solution is.

 

[gadfly56]

Per IBC;

Our clients are used to using multiple station smoke alarms in apartments, but no smoke alarms meet the new 520 Hz rule. We're trying to figure out what the least expensive solution is.

What is driving the 520 Hz requirement? It doesn't appear to be in the IBC. Under IBC, apartments are an R-2 occupancy. You could go with section 907.2.10.7 which allows the use of a fire alarm system instead of smoke alarms. Then you use an intelligent sounder base. That base activates only when the associated smoke detector is activated. I think you can also program bases in clusters so all the bases in a dwelling unit will activate if any of the smoke detectors in the unit activate. That way you can run power to all the bases at once.

 

[JoeStillman]

What is driving the 520 Hz requirement? It doesn't appear to be in the IBC. Under IBC, apartments are an R-2 occupancy. You could go with section 907.2.10.7 which allows the use of a fire alarm system instead of smoke alarms. Then you use an intelligent sounder base. That base activates only when the associated smoke detector is activated. I think you can also program bases in clusters so all the bases in a dwelling unit will activate if any of the smoke detectors in the unit activate. That way you can run power to all the bases at once.

520 Hz may not be in the IRC, but it definitely is for R-2 apartments in New Jersey. It's in the 2021 IBC: 907.5.2.1.3.2.

Some R-2 occupancies don't require a fire alarm system (for example, where there are no interior corridors, and each apartment has its own egress access). But if a system is required, you need 520 Hz and the smoke alarms have to initiate it.

Our specs have always offered the addressable-as-multi-station option, but nobody has been able to beat the price of smoke alarms - until now.

 

[gadfly56]

520 Hz may not be in the IRC, but it definitely is for R-2 apartments in New Jersey. It's in the 2021 IBC: 907.5.2.1.3.2.

Some R-2 occupancies don't require a fire alarm system (for example, where there are no interior corridors, and each apartment has its own egress access). But if a system is required, you need 520 Hz and the smoke alarms have to initiate it.

Our specs have always offered the addressable-as-multi-station option, but nobody has been able to beat the price of smoke alarms - until now.

You're a little ahead of the curve since the final adoption is effective in March, 2023. We just got notice from the Code Communicator of the formal adoption. But still, it is going to be a game changer. Simplex finally has a problem that now matches the solution they've been peddling for so long! Inspection, testing, and maintenance on these systems is going to be a nightmare, however.

 

[Strathead]

Drury Hotels, who design and build their own hotels, (5 per year), have required 520 Hz for at least 5 years in their projects. I built the Gainesville one in 2018 I think it was.

 

[gadfly56]

Drury Hotels, who design and build their own hotels, (5 per year), have required 520 Hz for at least 5 years in their projects. I built the Gainesville one in 2018 I think it was.

How did they address it, and with whose product?

 

[Strathead]

How did they address it, and with whose product?

We used Simplex, rooms were addressable sounder 520hz sounder bases, so with Simplex, you install a 24 volt constant and the SLC turns on the horn, if I remember, I cant remember how the rooms with strobes triggered. I do remember 5 rooms had CO and needed temporal code 4. We had to run a weird loop for that.