To help prevent CO problems and reduce the risk of CO poisoning:
Clean chimneys and flues yearly. Keep them free of debris,
leaves, and nests for proper air flow. Also, have a professional
check for rust and corrosion, cracks or separations. These
conditions can prevent proper air movement and cause
backdrafting. Never cap or cover a chimney in any way that
would block air flow.
Test and maintain all fuel-burning equipment annually. Many local
gas or oil companies and HVAC companies offer appliance
inspections for a nominal fee.
Make regular visual inspections of all fuel-burning appliances.
Check appliances for excessive rust and scaling. Also check the
flame on the burner and pilot lights. The flame should be blue. A
yellow flame means fuel is not being burned completely and CO
may be present. Keep the blower door on the furnace closed.
Use vents or fans when they are available on all fuel-burning
appliances. Make sure appliances are vented to the outside. Do
not grill or barbecue indoors, in garages or on screen porches.
Check for exhaust backflow from CO sources. Check the draft
hood on an operating furnace for a backdraft. Look for cracks on
furnace heat exchangers.
Check the house or garage on the other side of shared wall.
Keep windows and doors open slightly. If you suspect that CO is
escaping into your home, open a window or door. Opening
windows or doors can significantly reduce CO levels.
POTENTIAL SOURCES OF CO IN RESIDENTIAL
DWELLINGS
Fuel-burning appliances like:
portable heater, gas or wood
burning fireplace, gas kitchen range or cooktop, gas clothes dryer,
portable generators.
Damaged or insufficient venting:
corroded or disconnected
water heater vent pipe, leaking chimney pipe or flue, or cracked heat
exchanger, blocked or clogged chimney opening.
Improper use of appliance/device:
operating a barbecue grill,
portable generator or vehicle in an enclosed area (like a garage or
screened porch), or even your home.
550-0498
Pg. C-3
PLACEMENT OF CO ALARMS
THIS EQUIPMENT SHOULD BE INSTALLED IN ACCORDANCE
WITH THE NATIONAL FIRE PROTECTION ASSOCIATION'S
STANDARD 720 (National Fire Protection Association, Batterymarch
Park, Quincy, MA 02269).
For your information, the National Fire Protection Association's
Standard 720, reads as follows:
NFPA 720, 2009 Edition, Chapter 9, Section 9.4.1.1 Where required
by applicable laws, codes or standards for a specific type of
occupancy, approved single and multiple-station CO alarms shall be
installed as follows:
1) Outside of each separate dwelling unit sleeping area in the
immediate vicinity of the bedrooms.
2) On every occupiable level of a dwelling unit, including basements,
excluding attics and crawl spaces.
3) Other locations where required by applicable laws, codes or
standards.
The installation of additional CO alarms should result in a higher
degree of protection. Adding alarms to rooms that are normally
closed off from the required alarms increases the escape time
because the CO levels do not need to build to the higher level
necessary to force CO out of the closed room to the required alarms.
As a consequence, it is recommended that the householder consider
the installation of additional CO protection devices. However, it
should be understood that NFPA 720 does not require additional CO
alarms over and above those called for in Figures 2, 3, 4 and 5
where required CO alarms are shown.
Transient CO Problems:
transient or on-again-off-again CO
problems can be caused by outdoor conditions and other special
circumstances.
The following conditions can result in transient CO situations:
1) Excessive spillage or reverse venting of fuel appliances caused by
outdoor conditions such as:
Wind direction and/or velocity, including high, gusty winds. Heavy
air in vent pipes (cold/humid air with extended periods between
cycles).
Negative pressure differential resulting from the use of exhaust
fans.
Several appliances running at the same time competing for limited
fresh air.
Vent pipe connections vibrating loose from clothes dryers, furnaces
or water heaters.
Obstructions in or unconventional vent pipe designs which can
amplify the above situations.
2) Extended operation of unvented fuel burning devices (range,
oven, fireplace)
3) Temperature inversions, which can trap exhaust close to the
ground.
4) Car idling in an open or closed garage or near a home.
5) Portable generator used in an open or closed garage or near a
home.
Figure 1
Figure 1:
POTENTIAL SOURCES OF CO IN HOME.
These conditions can come and go, they are also hard to recreate
during a CO investigation.
Figure 4: IN DWELLING UNITS WITH MORE THAN ONE
SLEEPING AREA, A CO ALARM MUST BE PROVIDED TO
PROTECT EACH SLEEPING AREA.
Figure 3: A CO ALARM MUST BE LOCATED BETWEEN THE
SLEEPING AREA AND THE REST OF THE DWELLING UNIT.
Where to Locate the Required CO Alarms
. The major threat from
CO in a dwelling unit occurs at night when everyone is asleep.
Persons in sleeping areas can be threatened by CO levels in the
remainder of the unit; therefore, CO alarms are best located between
the bedroom areas and the rest of the unit as shown in Figure 3.
Figure 3
In dwelling units with more than one bedroom area or with
bedrooms on more than one floor, more than one CO alarm is
required, as shown in Figure 4.
Figure 4
Figure 2: A CO ALARM MUST BE LOCATED ON EVERY LEVEL OF
DWELLING UNIT, INCLUDING BASEMENT AND OUTSIDE SLEEP-
ING AREAS.
Figure 2