critical facts to keep in mind Regarding
First Alert 
smoke & carbon Monoxide AlarmS




1  –  It is a product of incomplete combustion of burning fossil fuels like, coal, charcoal, oil, gasoline, kerosene, natural and propane gas—all producing carbon monoxide (CO);

2  –  It is a fossil fuel-burning furnace, space heater, boiler, water heater, clothes dryer, fireplace, wood stove, grill, generator, motorcycle and automobile—malfunctioning;

3  –  It is all synthetic polymer products used in building your home, inside and outside; furnishing your home; or products you wear or use kept inside your home—burning when your home is on fire;

4  –  It is a colorless, odorless and tasteless, invisible and extremely toxic gas.  It can result in a headache, dizziness, weakness, vomiting, chest pain, confusion, unconsciousness, and ultimately DEATH.


Here are some Common Synthetic Polymers:

1  –  More than 20 different types of plastics—here are 8  –  acrylic, nylon, polystyrene, polyurethane, silicone, viscose rayon, polystyrene, polypropylene; 

2  –  More than 32 different commercial names—here are 8  –  Orlon, acrylic, Dacron, Plexiglass, Teflon, Naugahyde, Saran Wrap, Styrofoam;     

3  –  More than 60 different uses around the home—here are 14  –  toys, clothing, carpets, rubber products, drapes, faux wood products (trim, ceilings, flooring, etc.), sofa/chair cushions, acrylic paint, polyurethane varnish, lubricants, foam cups/packaging, video disks, faux glass.

In the 1960’s, before synthetic polymers existed in a home,
it would take about 30 minutes for a home fire (flashover) to take over a room.

In 2019—it can take less than 3 minutes before flashover.

In this mix—including many deadly gases and heat up to 1,400 degrees,
carbon monoxide is the most dangerous of the gases.

All of this together is making flashover time, escape time, collapse time and then to death much shorter! 




> Every 85 seconds a home fire starts somewhere in the United States.

It makes sense to have a number of top-notch working smoke and carbon monoxide alarms installed throughout your home.

> Your home is 10 times more likely to have a fire than to be burglarized.

> Most fire deaths are the result of smoke inhalation (up to 80%) and not  burning flesh.   In these deaths carbon monoxide was a major factor.

> A working photoelectric smoke and CO alarm system in your home is absolutely essential.


The Best Wireless
First Alert Smoke & Carbon monoxide alarm,
with voice & location 
is Here!


I have spent hundreds of hours over many, many months, gathering information about wireless smoke alarms—searching, reading, watching videos, asking questions, emailing, and talking on the phone to tech teams from some of the major manufacturing companies, and thinking.   I have consulted reviews by some of the leading consumer testing organizations like:

 The   |   |   |   |  

In addition, I have read scores of articles and reports, and viewed many videos, each covering in detail—research, testing, determined opinions by various experts, and legal decisions from fire prevention organizations (international, national, state and local), fire officials, and home inspection authorities. 

All have come to the same conclusion:  photoelectric smoke alarms provide superior protection across the broad spectrum of real-world fires, and electrochemical carbon monoxide alarms provide superior protection  at minimum levels and from all sources of CO. 

Here is a list of some of them:    

National Fire Protection Association (NFPA, USA)
Underwriters Laboratories (UL)
Fire Prevention Research Foundation (FPRF)
Rossen Reports, National Broadcasting Company (NBC)
First Alert, with subsidiaries in the United States and 7 other nations
BRK Brands, Inc.
Skip Walker, a certified inspector for ICC, CREIA, ASHI, and FCF
Judge David E. Schoenthaler, Mercer v. Pitway/BRK Brands (First Alert)
National Fire Protection Association (NFPA)
Consumer Product Safety Commission (CPSC)
National Institute for Standards and Testing (NIST)
Jay Fleming, Boston Deputy Fire Chief
American Society of Home Inspectors (ASHI)
Texas A & M University, Department of Construction Science
International Association of Fire Fighters (IAFF)



As of early 2019, this alarm below is the ONLY
combination smoke and carbon monoxide alarm 
that I could find

that has all the necessary safety, essential features including voice/location,

and best reviews, functional in one unit.

First Alert SCO501CN-3ST

Battery Operated, Combination
Smoke and carbon monoxide alarm with
voice warning and location

This eliminates the need for a wired system and the cost and time of running wires through the walls, floors and ceilings.  It also eliminates the possibility of someone cutting the power lines or power outages virtually shutting down the system.  Batteries are required, but batteries are also required to backup a wired system during a power failure.

Wireless Interconnected smoke alarms, with up to 18 enabled alarms connected, creates an excellent safety network—see note below.  All of the alarms in the system communicate with each other without wires or connections.  When one alarm sounds they all sound, alternately telling the location of the beginning fire and the sounding of the 85db horn.  This alarm will sound if it detects smoke even during power outages. It uses a secure radio frequency to communicate between alarms.

The units operate on a “mesh network” to integrate alarms for better safety and response in an emergency.  Why is this important?   Let’s say the signal is blocked from reaching the master bedroom alarm either by distance or some obstruction in the home.  With First Alert Wireless Interconnect, the mesh network of alarms re-routes and re- sends the signal via the other alarms, providing a greater chance all alarms will receive the signal.  The “mesh network” is
a more reliable means of wireless communication.

Radio Frequency Interconnect is a reliable and secure radio frequency communication between alarms—915 MHz frequency with 65,000 security codes and 3 channel frequency hopping.  This communication is perfect for linking alarms on different floors or in stairwells.  

This alarm is not hard-wired, nor can it be connected to your WiFi—it is wireless, depending on the use of 2-AA, 1.5V Alkaline batteries in each unit for power to run the system. 

They must be installed correctly matching “+” to “+” and “-” to “-“.  Regardless of the battery manufacturer’s suggested battery life, you must replace the batteries immediately once the unit starts “chirping” the low battery warning.  The “chirping” will continue once a minute for up to 30 days or until the batteries are replaced—but you should replace them immediately! 

When installing the batteries or replacing them, be sure to test the smoke alarm again.

This feature removes the hassle of replacing batteries from both the ceiling and the wall smoke alarms, making the task much easier.  There is no need to remove the alarms from their locking plates, mounted on the ceiling or wall, to replace the batteries.  Open the battery door, remove the used batteries and insert the new one.

There are 2 optional locking features:  one to lock the battery compartment and the other to lock the alarm to the mounting bracket.  You can use either locking feature independently or use them both together.  The optional locking features are designed to prevent unauthorized removal of the batteries or the alarm.  It is not necessary to activate the locks in single-family households where unauthorized battery or alarm removal is not a concern.

This is a vital safety feature.  It allows you to connect up to 16 alarms, of the same brand and number, within your home.  All alarms in the system communicate with each other without wires or connectors.  Should 1 alarm sound off, the remaining alarms will trigger simultaneously and providing an early warning to alert you and your family of the present danger.

Each of the alarms can be programmed to 1 of 11 locations, plus “no location” if none is chosen.  The locations are:  basement, kitchen, master bedroom, guest bedroom, living room, dining room, family room, office, utility room, hallway, and no location.

If the fire and smoke sets off the alarm in the family room, it will be announced with the voice location on all the connected alarms.  It will say:  “Warning, evacuate, smoke in the family room!”  The voice warning alarm has been tested and proven, to wake children who usually sleep soundly, and senior adults who may have hearing difficulties, better than standard alarms without the voice feature.

Repeatedly alternating, with the voice location warning, is a 85db horn.

This feature with a lower and varying horn frequency, makes it easier for elderly family members, with normal age related hearing loss, to hear the horn.  It’s horn is solid state rated at 85db at 10 feet,  sweeps through the 2200-3400 Hz range and should be capable of self restoring.   It sounds intermittently between the voice, with warning and location. 

This photoelectric smoke alarm is more responsive, in both testing and real-fire settings, than Ionization technology smoke alarms.  It reduces nuisance alarms.  The research and testing demonstrates that when all factors are taken into account, i.e.; how often each alarm gets disabled due to nuisance tripping, how they respond across the full spectrum of fires.  100% of the time, photoelectric alarms have a clear advantage over ionization alarms.

Do not use  smoke alarms with Ionization technology.  They are notorious for false alarms and frequently fail to respond to smoke in a timely fashion.   They repeatedly respond to boiling liquids on the stove, toast in the toaster, showers in a nearby bathroom, or hot air with steam as when you open the oven.  The homeowners then, in exasperation and frustration, remove the batteries, and the result?  In approximately 1/3 of all US fire deaths, these smoke alarms are disabled because the batteries have been removed.   A forgotten, but non-functioning ionization smoke alarm is a dangerous smoke alarm.

This unit also features a fully insect-screened smoke sensing chamber and a visual LED power-on indicator confirming that the unit is receiving power or is in alarm mode.

It is also tamper resistant, at the user’s option, locking the alarm to the mounting bracket to prevent removal of the battery and or the alarm.

Monitors CO levels accurately from a variety of sources.

This photoelectric smoke alarm has Optipath 360 Technology providing 360 degrees of direct access of the smoke to the smoke sensor.

The button on the smoke alarm operates as:  a mute button, silencing unnecessary or false alarms immediately for several minutes; a testing button to see if the alarm is fully functional; a retesting button to test the alarm when in silence mode; a button to clear the latching features; and a temporary silencing of the low battery “chirp” for up to 8 hours giving you time to replace the low batteries.

1) Alarm Latch:  easily identifies initiating alarm even after alarm condition has subsided.  2) Battery Latch:  identifies which alarm unit is in low battery condition.

There are 2 parts used to install each alarm—a gasketless base for easy installation, and a mounting bracket that keeps the alarm secure and over a wide rotation range to allow for perfect alignment of the alarm.  The alarm is designed for wall or ceiling and also includes anchors and screws.   Consult the PDF Manual for placement as outlined.

Size:  Circular 5 X 5 X 2 inches
Weight:  1 pound
Temperature Range:  40 degrees F (4 deg C) and 100 degrees F (38 deg C)
Humidity Range:  10-95% relative humidity (RH)
Compliant:  UL217, UL2034, FCC, CSFM, NFPA 72, NFPA 101 and other agencies that model their codes after the same agencies.  It meets building codes where battery operated Photoelectric smoke alarms with wireless interconnect, voice
location and silence features are required and with model building codes published by the ICC.  Always check your state and local building codes.

End of Life Signal provides audible notification alarm, at the 7-year limit, that the unit needs to be replaced.

The  BRK SCO501CN-3ST comes with a 7-year limited warranty, from the date of purchase—keep your dated receipt.  This product will be free from defects in material and workmanship.   BRK Brands, Inc., the maker of First Alert products, at its option will repair or replace this product or any component of the product found to be defective during the warranty period.

There is a 10-page Manual.   You will need it for setup and maintenance.



Observations:  82% Average Positive Comments from a Variety of Sources

>  Grandma is deaf and now happy, because she can hear the voice with location.
>  Peace of mind for seniors and our old house—WE CAN HEAR THE ALARM!
>  It’s a high quality product, just as described and recommended,
>  This is a genius alarm, built for my family’s safety.
>  The interconnected, wireless function makes installation a breeze.
>  Our kids were awake and out of bed in 10 seconds during the night-time test.
>  One of the best products ever invented, a fabulous “must” for every home.




Check Them Out  

No electrician to hire and no
wires to run through walls,
ceilings and floors to the circuit



All of the units are interconnect to
make a safety network—no wires
and no WiFi, only batteries.


This alarm depends solely on
battery power—2 – AA, 1.5V , it is

Makes the removal and the
replacement of batteries a much
easier task, whether the alarms
have been placed on the ceilings
or walls.


Optional locking is designed to
prevent unauthorized removal
of either the batteries or the
alarm, or both.

Up to 16 alarms can communicate
with each other providing the
same safe and full message—an
early warning of what and where
the danger is.


Each alarm can be programmed to
up to 11 locations—when the alarm
goes off it might say:  “Warning,
evacuate, smoke in the family
room!” sounding the solid state
horn intermittently between the
voice with warning and location.


Has a 100% clear advantage over
ionization technology—-both in
nuisance tripping and in
responding in a timely fashion
across the full spectrum of fires.


Monitors carbon monoxide (CO)
levels accurately from a variety of
sources—heat pump, furnace,
water heater, clothes dryer, grill,
fireplace, generator, motorcycle,
automobile and more.


Provides 360 degrees of direct
access for the smoke as it enters
the alarm and moves toward the
the smoke sensor.


The alarm button operates as:   a
mute button, silencing unnecessary
or false alarms;  a testing button to
determine the functionality of the
alarm;  a button to clear the latching
features;  and a button to silence
a “low battery” chirp for up to 8


Alarm Latch:  to identify initiating
alarm and the Battery Latch:  to
identify which alarm unit is in “low
battery” condition.


The gasketless base and the
mounting bracket, over a wide
range, perfectly align the alarm to
either the ceiling or the wall.


Size:  Circular 5x5x2 inches
Weight:  1 pound
Color:  white
Compliant with most building
codes—always consult state and
local building codes.


Signal provides audible notice at
7-year limit—replace unit. 




The SCO501CN-3ST comes with
a 7-year limited warranty, from
the date of purchase—keep your


Manual is included in the shipping
with the alarm—you will need it
for setup and maintenance. 

Most are from customers/users
and other sources and have great value for online shoppers.