SAFETY PRECAUTIONS
1-3
(a) 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
finished grade in the area of the venting, including but not limited to decks and porches, the following
requirements shall be satisfied:
1. INSTALLATION OF CARBON MONOXIDE DETECTORS. At the time of installation of the side wall
horizontal vented gas fueled equipment, the installing plumber or gasfitter shall observe that a hard wired
carbon monoxide detector with an alarm and battery back-up is installed on the floor level where the gas
equipment is to be installed. In addition, the installing plumber or gasfitter shall observe that a battery
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 qualified licensed professionals for the
installation of hard wired carbon monoxide detectors.
a. 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 floor level.
b. 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, however, that during said thirty (30) day period, a battery operated carbon monoxide
detector with an alarm shall be installed.
2. 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
certified.
3. SIGNAGE. A metal or plastic identification 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".
4. 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.
(b) EXEMPTIONS: The following equipment is exempt from 248 CMR 5.08(2)(a)1 through 4:
1. 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
2. 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.
(c) 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 system components with the equipment, the instructions provided by the
manufacturer for installation of the equipment and the venting system shall include:
