Skip Navigation
 
ALT
ALT
ALT
 

This table is used for column layout.
 
 
 
Smoke & Carbon Monoxide Detector Requirements
A Guide to the Massachusetts…
Smoke &
Carbon Monoxide
Requirements
…when Selling a Oneor
Two-Family Residence
FIRE SERVICES


     


 

Department of Fire Services
PO Box 1025 • Stow, MA 01775 • 978-567-3300
M.G.L. c 148 s. 26F - The Law
Massachusetts General Law, chapter 148 section 26F
mandates that upon the sale or transfer of certain homes,
the seller must install approved smoke detectors. These
requirements apply to residences that were built or modified
prior to creation of the Massachusetts State Building Code
(January 1, 1975). If a building has undergone renovation,
addition or modification after Jan. 1, 1975, the date of the
building permit determines the smoke detector requirements
of the building code.
Although the transfer law applies to residences with five or
less residential units, this pamphlet will focus only on oneand
two-family homes.
Verification
After a successful inspection for smoke detector compliance,
the local fire department will issue a Certificate of
Compliance indicating that the residence meets the smoke
detector requirements.
Although the law applies to homes built prior to the date
of the building code (Jan. 1975), it is industry practice that
most purchase and sales agreements, and many mortgage
companies require that the seller, as a condition to sell or
transfer, obtain a Certificate of Compliance issued by the
local fire department, even if the home was permitted or
modified after 1975.
Smoke Detector Requirements
In general, the requirements for smoke detectors vary
depending on when the residence was constructed. For
example, some residences may require battery-powered
detectors, others might need interconnected hard-wired
detectors only or a combination of both. Others might need
interconnected hard-wired detectors with battery backup.
On April 5, 2010, a significant change in the Massachusetts’
smoke detector requirements will become effective for
all residences subject to MGL c. 148, s. 26F upon sale or
transfer. Now, all smoke detectors installed within 20 feet
of kitchens or bathrooms (containing a bathtub or shower)
will be required to be photoelectric detectors. The risk of
nuisance alarms from steam and cooking is lower with
photoelectric only detectors. All installed smoke detectors
outside of 20 feet of kitchens or bathrooms (containing a
bathtub or shower) must utilize either:
• A DUAL detector (containing both ionization
and photoelectric technologies); OR
• Two separate detectors (one photoelectric
and one ionization).
In residences not subject to MGL c. 148, s. 26F (built after
Jan. 1975), the smoke detector upgrade is recommended, but
is not required by law.
Photoelectric vs. Ionization Technologies
Ionization smoke detectors:
• Use radiation to detect smoke.
• More effective in detecting flaming fires.
• Increased risk of nuisance alarms caused by steam or
cooking smoke.
Photoelectric smoke detectors:
• Use light to detect smoke.
• More effective in detecting smoldering fires, which
have been attributed to more fires involving death.
• Low voltage or wireless low voltage systems only use
photoelectric detectors.
Carbon Monoxide Alarms
Massachusetts General Law, chapter 148 section 26F and
527 CMR 31 mandates that upon the sale or transfer of
any residence, the local fire department must inspect the
residence for carbon monoxide alarm compliance. After a
successful inspection, the local fire department will issue a
Certificate of Compliance indicating that the residence meets
the carbon monoxide alarm requirements.
Carbon Monoxide Alarm Requirements
Since March 31, 2006, carbon monoxide alarms have been
required in all residences that have either: fossil fuel burning
equipment or an attached enclosed garage. This law applied
to all such residences whether or not the residence is being
sold or transferred.
What is Fossil Fuel Burning Equipment?
Fossil fuel burning equipment is any device, apparatus
or appliance that is designed or used to consume fuel of
any kind which emits carbon monoxide as a by-product
of combustion. Some examples of a fossil fuel burning
equipment include: water heaters, oil or gas furnaces, wood
or gas fireplaces, wood pellet stoves, gas clothes dryers, or gas
cooking stoves.
How Will I Know What I Need?
The word “typical” is used in the following guidelines only
for purposes of illustration. The actual requirements may
depend on when the building permit for the residence
was actually applied for and if there have been any major
renovations, additions or modifications. It is best to check
with your local fire department for detailed guidance.
Typical one- and two-family residences
built before January 1, 1975:
• Smoke detectors are required as follows:
 On every habitable level of the residence.
 On the ceiling at the base of each stairway.
 On the ceiling outside of each separate sleeping
area.
The smoke detectors may either be battery
powered, hardwired or a combination of the two.
 If the smoke detector is located within 20 feet of
a kitchen or bathroom (containing a bathtub or
shower), the smoke detector will be required to be
a photoelectric detector.
 If the smoke detector is outside of 20 feet of a
kitchen or a bathroom (containing a bathtub or
shower) you must utilize either:
 A dual detector (containing both ionization and
photoelectric technologies); OR
Two separate detectors (one photoelectric and
one ionization).
• Low voltage household warning systems are
exempt from the dual detection requirement.
• Carbon monoxide alarms are required
as follows:
 On every level of the residence, including
habitable portions of basements and attics and
must be located within 10 feet of each
bedroom door.
 Combination detectors (photoelectric smoke
and carbon monoxide detector) may be used
if the detector is within 20 feet of a kitchen or
bathroom (containing a bathtub or shower).
 Combination detectors (ionization smoke and
carbon monoxide detector) may be used if the
detector is outside of 20 feet of a kitchen or
bathroom (containing a bathtub or shower).
May be either: battery powered, plug-in with
battery backup, hardwired with battery backup, or
system type.
 Follow the manufacturer’s instructions for
placement.
Typical one- and two-family residences
permitted between 1975 and August 27, 1997:
• Smoke detectors are required as follows:
 One smoke detector on every habitable level of
the residence.
 One smoke detector on the ceiling at the base of
each stairway.
 One smoke detector on the ceiling outside of
each separate sleeping area.
 A minimum of one smoke detector must be
installed for every 1,200 square feet of living
space per level.
 Must be hardwired interconnected smoke
detectors.
• Carbon monoxide alarms are required as
follows:
 On every level of the residence, including
habitable portions of basements and attics and
must be located within 10 feet of each bedroom
door.
 Combination detectors (photoelectric smoke
and carbon monoxide detector) may be used
anywhere.
 Combination detectors (ionization smoke and
carbon monoxide detector) may be used if the
detector is outside of 20 feet of a kitchen or
bathroom (containing a bathtub or shower).
May be either: battery powered, plug-in with
battery backup, hardwired with battery backup, or
system type.
 Follow the manufacturer’s instructions for
placement.
Typical one- and two-family residences
permitted after August 27, 1997:
• Smoke detectors are required as follows:
 One smoke detector on every habitable level of
the residence.
 One smoke detector at the base of each stairway.
 One smoke detector outside of each separate
sleeping area.
 One smoke detector inside every bedroom.
 A minimum of one smoke detector must be
installed for every 1,200 square feet of living
space per level.
 Must be hardwired and interconnected smoke
detectors with battery backup.
 If the smoke detector is within 20 feet of a
kitchen or bathroom (containing a bathtub or
shower), the smoke detector is required to be a
photoelectric detector.
• Carbon monoxide alarms are required as
follows:
 On every level of the residence, including
habitable portions of basements and attics and
must be located within 10 feet of each bedroom
door.
 Combination detectors (photoelectric smoke
and carbon monoxide detector) may be used
anywhere.
 Combination detectors (ionization smoke and
carbon monoxide detector) may be used if the
detector is outside of 20 feet of a kitchen or
bathroom (containing a bathtub or shower).
May be either: battery powered, plug-in with
battery backup, hardwired with battery backup, or
system type.
 Follow the manufacturer’s instructions for
placement.
Typical one- and two-family residences
permitted on or after January 1, 2008:
• Smoke detectors are required as follows:
 One smoke detector on every habitable level of
the residence.
 One smoke detector at the base of each stairway.
 One smoke detector outside of each separate
sleeping area.
 One smoke detector inside every bedroom.
 A minimum of one smoke detector must be
installed for every 1,200 square feet of living
space per level.
 Must be hardwired and interconnected smoke
detectors with battery backup.
 If the smoke detector is within 20 feet of a
kitchen or bathroom (containing a bathtub or
shower), the smoke detector is required to be a
photoelectric detector.
 If the smoke detector is outside of 20 feet of
a kitchen or a bathroom (containing a bathtub
or shower), the smoke detector is required to be
either a photoelectric detector or a dual detector
(containing both ionization and photoelectric
technologies).
• Carbon monoxide alarms are required
as follows:
 On every level of the residence, including
habitable portions of basements and attics and
located within 10 feet of each bedroom door.
 Combination detectors (photoelectric smoke and
carbon monoxide detector) may be used.
 Must be hardwired and interconnected with
battery backup. (May be separately wired from
the existing smoke detection system.)
 Follow the manufacturer’s instructions for
placement.
• Heat detectors are required as follows:
 Must have a single heat detector in any garage
attached to or under the residence.
 Must be hardwired and interconnected with or
without battery backup to the existing smoke
detection system.
 Heat detectors are not required in older homes
unless renovation, addition or modification occurs
after Jan. 1, 2008.
How Will I Get a
Certificate of Compliance?
After you have a closing date:
• Contact the local fire department to schedule an
inspection of your smoke and carbon monoxide
detectors right away. Don’t wait until the last minute!
• Fees are determined by each city/town.
Prior to the arrival of the fire department:
• Make sure that your posted street number is
visible from the street (MGL c.148 § 59);
• Make sure that you have the proper type of
detectors.
 The local fire department may require that they be
taken down for compliance verification.
 Make sure that all detectors are installed in the
proper locations.
 Make sure that all detectors are working properly.
• After passing the inspection, the local fire
department will issue your Certificate of
Compliance.
This document will probably be required at the
closing and is only valid for 60 days.
How Do I Know which
Kind of Smoke Detector I Have?
A new detector should be marked on the outside of the
package to indicate if it uses ionization or photoelectric
technology.
For older or existing detectors you will need to remove the
smoke detector and look on the backside.
• The date of manufacture should be on
the back; if not, the detector is most likely
outdated and should be replaced to comply
with the regulation.
• It is an ionization smoke detector if the word
“AMERICIUM” or the following symbol is
on the back:
Can I Still Have Ionization
Smoke Detectors if I Am Not Selling or
Transferring My Home?
• Yes. The requirements in the new regulation only
apply upon the sale or transfer of the residence.
• Even though the technology has changed, ionization
detectors are still reliable.
• However, the risk of nuisance alarms from steam
and cooking is higher with ionization detectors,
particularly if located within 20 ft of a kitchen or
bathroom.
Are Combination Carbon Monoxide
& Smoke Detectors Permitted?
• Yes. Combination carbon monoxide and smoke
detectors are permitted.
• They must have both a tone and simulated voice
alarm to distinguish the type of emergency. Carbon
monoxide detectors are required regardless of a sale
or transfer.
• Combination ionization and CO detectors cannot be
used within 20 ft of a kitchen or bathroom
Are There Other Recommendations?
The State Fire Marshal’s Office recommends:
• Test your smoke and CO detectors monthly
and replace the batteries twice a year.
REMEMBER, when you change the clocks,
change the batteries.
 Unless otherwise recommended by the
manufacturer’s published instructions, no smoke
detectors (battery operated or hard-wired smoke
detectors only!) shall remain in service after 10
years from the date of manufacture.
February 2010
FIRE SERVICES