NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
Note: The following requirements reference various Massachusetts
and national codes not contained in this document.
Requirements for the Commonwealth of Massachusetts
For all side wall horizontally vented gas fueled equipment installed in every
dwelling, building or structure used in whole or in part for residential
purposes, including those owned or operated by the Commonwealth and
where the side wall exhaust vent termination is less than seven (7) feet
above fi nished grade in the area of the venting, including but not limited
to decks and porches, the following requirements shall be satisfi ed:

Installation Of Carbon Monoxide Detectors

At the time of installation of the side wall horizontal vented gas fueled
equipment, the installing plumber or gasfi tter shall observe that a hard
wired carbon monoxide detector with an alarm and battery back-up is
installed on the fl oor level where the gas equipment is to be installed.
In addition, the installing plumber or gasfi tter shall observe that a bat-
tery operated or hard wired carbon monoxide detector with an alarm is
installed on each additional level of the dwelling, building or structure
served by the side wall horizontal vented gas fueled equipment. It shall
be the responsibility of the property owner to secure the services of
qualifi ed licensed professionals for the installation of hard wired carbon
monoxide detectors.
In the event that the side wall horizontally vented gas fueled equipment
is installed in a crawl space or an attic, the hard wired carbon monoxide
detector with alarm and battery back-up may be installed on the next
adjacent fl oor level.
In the event that the requirements of this subdivision can not be met at
the time of completion of installation, the owner shall have a period of
thirty (30) days to comply with the above requirements; provided, how-
ever, that during said thirty (30) day period, a battery operated carbon
monoxide detector with an alarm shall be installed.

Approved Carbon Monoxide Detectors

Each carbon monoxide detector as required in accordance with the
above provisions shall comply with NFPA 720 and be ANSI/UL 2034
listed and IAS certifi ed.

Signage

A metal or plastic identifi cation plate shall be permanently mounted to
the exterior of the building at a minimum height of eight (8) feet above
grade directly in line with the exhaust vent terminal for the horizontally
vented gas fueled heating appliance or equipment. The sign shall read, in
print size no less than one-half (1/2) inch in size, “GAS VENT DIRECTLY
BELOW. KEEP CLEAR OF ALL OBSTRUCTIONS.”

Inspection

The state or local gas inspector of the side wall horizontally vented gas
fueled equipment shall not approve the installation unless, upon inspection,
the inspector observes carbon monoxide detectors and signage installed
in accordance with the provisions of 248 CMR 5.08(2)(a)1 through 4.

Exemptions

The following equipment is exempt from 248 CMR 5.08(2)(a)1 through 4:
• The equipment listed in Chapter 10 entitled “Equipment Not Required
To Be Vented” in the most current edition of NFPA 54 as adopted by
the Board; and
• Product Approved side wall horizontally vented gas fueled equipment
installed in a room or structure separate from the dwelling, building
or structure used in whole or in part for residential purposes.

MANUFACTURER REQUIREMENTS

Gas Equipment Venting System Provided

When the manufacturer of Product Approved side wall horizontally
vented gas equipment provides a venting system design or venting sys-
tem components with the equipment, the instructions provided by the
manufacturer for installation of the equipment and the venting system
shall include:
• Detailed instructions for the installation of the venting system design
or the venting system components; and
• A complete parts list for the venting system design or venting sys-
tem.

Gas Equipment Venting System NOT Provided

When the manufacturer of a Product Approved side wall horizontally
vented gas fueled equipment does not provide the parts for venting the
fl ue gases, but identifi es “special venting systems”, the following require-
ments shall be satisfi ed by the manufacturer:
• The referenced “special venting system” instructions shall be included
with the appliance or equipment installation instructions; and
• The “special venting systems” shall be Product Approved by the
Board, and the instructions for that system shall include a parts list
and detailed installation instructions.
A copy of all installation instructions for all Product Approved side wall
horizontally vented gas fueled equipment, all venting instructions, all
parts lists for venting instructions, and/or all venting design instructions
shall remain with the appliance or equipment at the completion of the
installation.
• Installation and repair must be done by a plumber or gas fi tter licensed
in the Commonwealth of Massachusetts.
• The fl exible gas line connector used shall not exceed 36 inches (92
centimeters) in length.
• The individual manual shut-off must be a T-handle type valve.
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