Is one smoke detector ever ok

[Bob Elliott]

I went to a exclusive high rise development today with state of the art sprinkler system installed in every room and a siren near the front door.
Heck.. the stairwells even have call for help intercoms.
This is the second time in the last couple of weeks I have inspected here and apparently all of the units have only one lonely smoke detector.
Are they excused from needing one for each bedroom and near the front door because of the sprinklers.
I say no
What say you

[Buck Hartley, CMI]

I say NO!!!

[dbush]

Robert, do the sprinklers have heat sensors installed on every sprinkler head? That would be the exception I think. I would still recommend a smoke detector in every living space (read bedroom) because the noise would wake someone up much better than getting wet.

[Christopher Currins]

In Illinois in multi family homes a smoke detector must be installed in the basement, at the head of open stairs at each floor level, at the door leading to enclosed stairs at each floor level, within 15 feet of each living units sleeping area, in each bedroom. I see no exceptions to sprinkler systems. I could be wrong. Obviously, what if the sprinkler sytem failed?

[Bob Elliott]

Chris I agree.
My reason is different though.
Most people die from smoke inhalation, he types with cigarette planted in mouth.
Here is a cool link I found a while back.
Check it out as it nis rich with code .
http://www.amlegal.com/nxt/gateway.d...gal:chicago_il

[Christopher Currins]

Originally Posted by relliott

Chris I agree.
My reason is different though.
Most people die from smoke inhalation, he types with cigarette planted in mouth.
Here is a cool link I found a while back.
Check it out as it nis rich with code .
http://www.amlegal.com/nxt/gateway.d...gal:chicago_il

Good site Bob. How updated is it? I agree with the smoke inhalation...by the time the sprinklers activated it might be to late...or you could sleep through it and still die. It could also make escaping more difficult.

[Dominic J. Maricic]

How big was the place? Was it a studio?

[Bob Elliott]

I am not sure how updated it is as I just rediscovered it when looking for a reason to allow one smoke detector.
Lots of good fire code info though
still it is Chicago code which means nothing in our world

[Bob Elliott]

Where is the language for needing a smoke detector at the front door as some of the national sites I am looking at only worry about bedrooms.

[Barry Adair]

This is what goes in my reports (Note sleeping area/room not just bedroom)

NFPA

Installation and maintenance tips

• Install smoke alarms on every level of your home, including the basement, making sure that there is an alarm outside every separate sleeping area. New homes are required to have a smoke alarm in every sleeping room and all smoke alarms must be interconnected.
• Hard-wired smoke alarms operate on your household electrical current. They can be interconnected so that every alarm sounds regardless of the fire's location. This is an advantage in early warning, because it gives occupants extra time to escape if they are in one part of the home and a fire breaks out in another part. Alarms that are hard-wired should have battery backups in case of a power outage, and should be installed by a qualified electrician.
• If you sleep with bedroom doors closed, have a qualified electrician install interconnected smoke alarms in each room so that when one alarm sounds, they all sound.
• If you, or someone in your home is deaf or hard of hearing, consider installing an alarm that combines flashing lights, vibration and/or sound.
• Mount smoke alarms high on walls or ceilings (remember, smoke rises). Ceiling mounted alarms should be installed at least four inches away from the nearest wall; wall-mounted alarms should be installed four to 12 inches away from the ceiling.
• If you have ceilings that are pitched, install the alarm near the ceiling's highest point.
• Don't install smoke alarms near windows, doors, or ducts where drafts might interfere with their operation.
• Never paint smoke alarms. Paint, stickers, or other decorations could keep the alarms from working.

Sensing systems
Most smoke alarms use one of two common sensing systems for detecting a fire.

• Ionization-type smoke alarms have a small amount of radioactive material between two electrically charged plates, which ionizes the air and causes current to flow between the plates. When smoke enters the chamber, it disrupts the flow of ions, thus reducing the flow of current and activating the alarm.
• Photoelectric-type alarms aim a light source into a sensing chamber at an angle away from the sensor. Smoke enters the chamber, reflecting light onto the light sensor; triggering the alarm.
• Ionization smoke detection is generally more responsive to flaming fires and photoelectric smoke detection is generally more responsive to smoldering fires. Both types of technologies have improved home fire safety.

Impact on NFPA Codes
NFPA has convened the Task Group on Smoke Detection Technologies, a task group of NFPA’s Technical Committee on Single- and Multiple-Station Alarms and Household Fire Alarm Systems to review current research and other sources of information to determine the best methods and practices for detecting smoke and to determine if changes may be needed in the next edition of the National Fire Alarm Code. The task group will consider a range of issues including false alarms and the speed of detector response.
In the interim it is recommended that both types of detection be installed in homes.
NFPA does not test, label or approve any products.
Updated: 7/07

[Barry Adair]

While we're on this subject maybe a coupon for alarms and batteries should be included in the Home Head Start Guide.

Nick,
What do you think?

[msylvester]

Barry, good point.

[Bob Elliott]

Thanks Barry.
I was sure about there being a requirment for them to be placed at the bottom and top of stairs, and near entry doors , but do not see it.

[sstowe]

Barry's reply is good and that is the general recommendation per NFPA 72 which in the case of smoke detectors specifies how smokes are to be installed if required. NFPA 101(Life Safety Code) specifies what type of fire alarms are required in different types of occupancies. A highrise is very likely to have different requirements than a standard residential unit.

Also the AHJ has final say on fire requirements no matter what the code says. I have seen some require less than code and some require much more.