What You Should Know About
and Indoor
  Prepared by
  The Christmas Seal Peopleฎ

What  You  Should

Know About


Appliances  and

Indoor Air Pollution

Hazards may be associated with almost all types of
appliances. The purpose of this booklet is to answer
some common questions you may have about the
potential for one specific type of hazard - indoor
air pollution - associated with  one class  of
appliances - combustion  appliances.
  Combustion appliances are those which burn
fuels for warmth, cooking, or decorative purposes.
Typical fuels are gas, both natural and liquefied
petroleum (LP); kerosene; oil; coal; and wood.
Examples of the appliances are space heaters,
ranges, ovens, stoves, furnaces, fireplaces, water
heaters, and clothes dryers. These appliances are
usually safe. However, under certain conditions,
these  appliances  can  produce combustion
pollutants that can damage your health, or even
kill you.
headaches, dizziness, sleepiness, and watery
eyes to breathing difficulties or even  death.
Similar effects may also occur because  of
common medical problems or other indoor air
  This  booklet was written: (1) to encourage the
proper use, maintenance, and installation of com-
bustion appliances; (2) to discuss the pollutants pro-
duced  by these appliances; (3) to describe how
these pollutants can affect your health; and (4) to
tell you  how you  can  reduce your exposure
to them.
This booklet has been prepared by the
U.S. Consumer Product Safety Commission,
the U.S. Environmental Protection Agency,
and the American Lung Associationฎ

Should  I be concerned

about indoor air pollution?

Yes. Studies have shown that the air in our homes
can be even more polluted than the outdoor air in
big cities. Because people spend a lot of time in-
doors, the quality of the air indoors can affect their
health. Infants, young children and the elderly are
a group shown to be more susceptible to pollutants.
People with chronic respiratory or cardiovascular
illness or immune system diseases are also more
susceptible than others to pollutants.
 Many factors determine whether pollutants  in
your home will affect your health. They include the
presence, use, and condition of pollutant sources,!
the level of pollutants both indoors and out, the
amount  of ventilation in your home, and your
overall health.                              ;
 Most homes have more than one source of indoor
air pollution. For example, pollutants come from
tobacco smoke, building materials, decorating pro-
ducts, home furnishings, and activities such  as
cooking, heating, cooling, and cleaning. Living in
areas with high outdoor levels of pollutants usually
results in high indoor levels. Combustion pollutants
are one category of indoor air pollutants.

What  are  combustion


Combustion pollutants are gases  or particles that
come  from burning  materials.  The combustion
pollutants  discussed  in this  booklet come from
burning  fuels  in appliances.  The common fuels
burned in these appliances are natural or LP gas,
fuel oil, kerosene, wood,  or coal. The types and
amounts of pollutants produced depend upon the
type of  applicance,  how well the appliance  is
installed, maintained, and vented, and the kind  of
fuel it uses. Some of the common pollutants pro-
duced from burning these fuels are carbon monox-
ide, nitrogen dioxide, particles, and sulfur dioxide.
Particles can have hazardous chemicals attached
to them. Other pollutants that can be produced by
some  appliances are unburned hydrocarbons
and aldehydes.

  Combustion always produces water vapor. Water
vapor is not usually considered a pollutant, but it
can act as one. It can result in high humidity and
wet surfaces.  These  conditions encourage the
growth of biological pollutants such as house dust
mites, molds, and bacteria.

Where do  combustion

pollutants come  from?

Combustion pollutants found indoors include: out-
door air, tobacco smoke, exhaust from car and
lawn mower internal combustion engines, and
some hobby activities such  as welding, wood-
burning, and soldering. Combustion pollutants can
also come from vented or unvented combustion
appliances. These appliances include space heaters,
gas ranges and ovens, furnaces, gas water heaters,
gas clothes dryers,  wood or coal-burning stoves,
and fireplaces. As a group these are called "com-
bustion appliances."

What  is  a  vented

appliance? What is an

unvented appliance?

Vented appliances are appliances designed  to  be
used with a duct, chimney, pipe, or other device
that carry the combustion pollutants outside the
home. These appliances can release large amounts
of pollutants directly into your home, if a vent is
not properly installed, or is blocked or leaking.
  Unvented appliances do not vent to the outside,
so they release combustion pollutants directly into
the home.
  Look at the box below for typical appliance pro-
blems that cause the release of pollutants in your
home. Many of these problems are  hard  for a
homeowner to identify. A professional is needed.

Typical Potential Problems
Central Furnaces Natural or
Room Heaters    Liquified
Gas Fireplaces    Petroleum
           Cracked heat exchanger
           Not enough air to burn
             fuel properly
           Defective/blocked flue
           Maladjusted burner
Central Furnaces  Oil
           Cracked heat exchanger
           Not enough air to burn
             fuel properly
           Defective/blocked flue
           Maladjusted burner
Central Heaters   Wood       Cracked heat exchanger
Room Heaters                Not enough air to burn
                             fuel properly
                            Defective/blocked flue    i
                            Green or treated wood

Central Furnaces  Coal        Cracked heat exchanger
Stoves                       Not enough air to burn
                             fuel properly
                            Defective/blocked flue
                            Defective grate

Room Heaters    Kerosene    Improper adjustment
Central Heaters               Wrong fuel (not K-l)
                            Wrong wick or wick height
                            Not enough air to burn
                             fuel properly           !
Water Heaters
Natural or
Natural or
Not enough air to bum
fuel properly
Defective/blocked flue
Maladjusted burner
Not enough air to burn
fuel properly
Maladjusted burner
Misuse as a room heater
Not enough air to burn
fuel properly
                           Defecth^locked flue
                           Green or treated wood
                           Cracked heat exchanger
                             or firebox

Can I use charcoal grills or

charcoal hibachis indoors?

No. Never use these appliances inside homes,
trailers,  truck-caps, or tents. Carbon monoxide
from burning and smoldering charcoal can kill you
if you use it indoors for cooking or heating. There
are about 25 deaths each year from the use of char-
coal grills and hibachis indoors.
NEVER burn charcoal inside homes, trailers,
tents, or other enclosures. The carbon monox-
ide can kill you.

What are  the health

effects of combustion


The health effects of combustion pollutants range
from headaches and breathing difficulties to death.
The health effects may show up immediately after
exposure or  occur after being exposed to the
pollutants for a long time. The effects depend upon
the type and amount of pollutants and the length

of time of exposure to them. They also depend
upon several factors related to the exposed person.
These include the age and any- existing health pro-
blems. There are still some  questions about the
level of pollutants or the period of exposure needed
to produce specific health effects. Further studies
to better define the release of pollutants from com-1
bustion appliances and  their health effects
are needed.
  The  sections below discuss  health  problems
associated  with  some   common  combustion
pollutants. These pollutants include carbon monox-
ide, nitrogen dioxide, particles, and sulfur dioxide.
Even if you are healthy, high levels of carbon
monoxide can kill you within  a short time. The
health effects of the other pollutants are generally
more subtle and are more  likely to affect suscep-
tible people. It is always  a good idea to reduce
exposure to combustion pollutants by using and
maintaining combustion appliances properly.

Carbon Monoxide:

Each year, according to CPSC, there are more than
200 carbon monoxide deaths related to the use of
all types of combustion appliances in the home. Ex-
posure to carbon monoxide  reduces  the blood's
ability to carry oxygen. Often a person or an en-
tire family may not recognize that carbon monox-
ide is poisoning them. The chemical is odorless and
some of the symptoms are similar to common
illnesses. This  is particularly dangerous because
carbon  monoxide's  deadly  effects  will  not
be recognized until it is too late to take action
against them.
  Carbon monoxide exposures especially affect un-
born babies, infants, and people with anemia or a
history of heart disease. Breathing low levels of the
chemical can cause fatigue and increase chest pain
in people  with chronic heart disease. Breathing
higher levels of carbon monoxide causes symptoms
such as headaches,  dizziness,  and weakness in
healthy people. Carbon  monoxide also causes
sleepiness, nausea,  vomiting,  confusion,  and
disorientation. At very high levels it causes loss of
consciousness and death.

Nitrogen Dioxide:

Breathing high levels of nitrogen dioxide causes ir-
ritation of the respiratory tract and causes shortness
of breath. Compared to healthy .people, children,
and individuals with respiratory illnesses such as
asthma, may be more susceptible to the effects of
nitrogen dioxide.
  Some studies have shown that children may have
more colds and flu when exposed to low levels of
nitrogen dioxide. When people with asthma inhale
low levels of nitrogen dioxide while exercising,
their lung airways can narrow and react more to
inhaled materials.


Particles suspended in the air can cause eye, nose,
throat,  and lung irritation. They can increase
respiratory symptoms, especially in people with
chronic lung disease  or  heart problems. Certain
chemicals attached to particles may cause lung
cancer, if they are inhaled. The risk of lung cancer
increases with the amount and length of exposure.
The health effects from inhaling particles depend
upon many factors, including the size of the parti-
cle and its chemical make-up.

Sulfur Dioxide:
Sulfur dioxide at low levels of  exposure can cause
eye, nose, and respiratory tract irritation. At high
exposure levels,  it causes  the lung airways to
narrow. This causes wheezing, chest tightness, or
breathing problems. People with asthma are par-
ticularly susceptible to the effects of sulfur diox-
ide.  They may have symptoms at levels that are
much lower than the rest of the population.
Other Pollutants:

Combustion may release other pollutants. They in-
clude unburned hydrocarbons and aldehydes. Lit-
tle is known about the levels of these pollutants
in indoor air and the resulting health effects.

What  do  I do if I  suspect

that combustion pollutants

are affecting my health?

If you suspect you are being subjected to
carbon  monoxide  poisoning get fresh aiir
immediately. Open windows and doors for more
ventilation, turn off any combustion appliances,
and leave the house. You could lose consciousness
and die from carbon monoxide poisoning if you do
nothing. It is also important to contact a doctor
IMMEDIATELY for a proper diagnosis. Remember
to tell your doctor that you suspect carbon monox-
ide poisoning is causing your problems. Prompt
medical attention is important.
  Remember that some symptoms from combustion
pollutants  - headaches, dizziness,  sleepiness,
coughing,  and  watery  eyes - may  also occur
because  of common medical problems. These
medical problems include colds, the flu, or allergies.
Similar symptoms may also occur because of other
indoor air pollutants. Contact your doctor for a pro-
per diagnosis.
  To help your doctor make the correct diagnosis,
try to have answers to the following questions:
• Do your symptoms occur only in the home? Do
  they disappear or decrease when you leave
  home, and reappear when  you  return?
• Is anyone else in your household complaining of
  similar symptoms, such as headaches, dizziness,,
  or sleepiness? Are they complaining of nausea,
  watery eyes,  coughing, or  nose and throat
• Do you always have symptoms?
• Are your symptoms getting worse?
• Do you often catch colds or get the flu?
• Are  you  using any combustion appliances in
  your home?
• Has anyone inspected your appliances lately? Are
  you certain they are working properly?

  Your doctor may take a blood sample to measure
the level of carbon monoxide in your blood if he
or she suspects carbon monoxide poisoning. This
sample will help determine whether carbon monox-
ide is affecting your health.
  Contact qualified appliance service people to
have your appliances inspected and adjusted if
needed. You should be able to find a qualified per-
son by asking your appliance distributor or your
fuel supplier. In some areas, the local fuel company
may be able to inspect and adjust the appliance.

How can I reduce  my

exposure  to combustion


Proper selection,  installation,  inspection and
maintenance  of your appliances are extremely
important in reducing your exposure to these
pollutants. Providing good ventilation in your home
and correctly using your appliance can also reduce
your exposure to these pollutants.
  Additionally, there are several different residen-
tial carbon monoxide detectors for sale. The CPSC
is encouraging the development of detectors that
will provide maximum protection. These detectors
would warn consumers of harmful carbon monox-
ide levels in the home. They may soon be widely
available to reduce deaths from carbon monoxide


• Choose vented appliances whenever possible.
• Only buy combustion appliances that have
  been tested and certified to meet current
  safety  standards. Examples  of certifying
  organizations are Underwriters Laboratories (UL)
  and the American Gas Association  (AGA)
  Laboratories. Look for a label that clearly shows
  the certification.
• All currently manufactured vented gas heaters
  are required by industry safety standards to
  have a safety shut-off device. This device helps
  protect you from carbon monoxide poisoning by
  shutting off an improperly vented heater.

Check your local and state building codes and
•fire ordinances to see if you can  use am
unvented space heater, if you consider pur--
chasing one. They are not allowed to be used
in some communities, dwellings, or certain rooms
in the house.                              :
If you must replace an unvented gas space
heater with another,  make it a new one,,
Heaters made after 1982 have a pilot light safety
system called an oxygen depletion sensor (ODS).
This system shuts off the heater when  there is
not enough fresh air, before the heater begins
producing large amounts of carbon monoxide.
Look for the label  that  tells  you that the
appliance has this safety system. Older heaters
will not have this protection system.
Consider buying gas  appliances  that have
electronic ignitions rather than pilot lights,,
These appliances are usually more energy  effi-
cient and eliminate the continuous low-level
pollutants from pilot lights.
Buy appliances that are the correct size for
the area you want to heat. Using the wrong size:
heater may produce more pollutants  in your
home and is not an efficient use of energy.
Talk to your dealer to determine the type anct
size of appliance you will need. You may wish
to write to the appliance manufacturer or asso-
ciation for more information on the appliance.
Some addresses are in the back of this booklet!

• All new woodstoves are EPA-certified to limit
  the amounts of pollutants released into the
  outdoor air. For more information on selecting,
  installing,  operating, and maintaining  wood-
  burning stoves, write to the EPA Wood Heater
  Program. Their address is in the back of this
  booklet. Before buying a woodstove check your
  local laws about  the installation  and use of

Proper Installation
• You should have your  appliances profes-
  sionally installed. Professionals should follow
  the installation directions and applicable building
  codes. Improperly installed appliances can release
  dangerous pollutants in your home and may
  create a fire hazard. Be sure that the installer
  checks for backdrafting on all vented appliances.
  A qualified installer knows how to do this.

• To reduce indoor air pollution, a good supply
  of fresh outdoor air is needed. The movement
  of air into and out of your home is very impor-
  tant. Normally, air comes through cracks around
  doors and windows. This air helps reduce the
  level of pollutants indoors. This supply of fresh
  air is also important to help carry pollutants up
  the chimney, stovepipe, or flue to the outside.

• Keep doors open to the rest of the house from
  the room where you are using an unvented
  gas space  heater or  kerosene heater, and
  crack open a window. This allows enough air
  for proper combustion and reduces the level of
  pollutants, especially carbon monoxide.
• Use a hood fan, if you are using a range. They
  reduce the level of pollutants you breath, if they
  exhaust to the outside. Make sure that enough
  air is coming into  the house when you use an
  exhaust fan. If needed, slightly open a door or
  window, especially if other appliances are in use.
  For proper operation of most combustion
  appliances  and their venting system, the air
  pressure in the house should be greater than that
  outside. If  not, the vented appliances could
  release combustion  pollutants into the  house
  rather than outdoors. If you suspect that you
  have this problem you may need the help of a
  qualified person to solve it.                  ;
• Make sure that your vented appliance has the
  vent connected and that nothing is blocking
  it. Make sure there are no holes or cracks in the
  vent. Do not vent gas clothes dryers or water1
  heaters into  the house for heating. This is
  unsafe.                                   i
• Open the stove's damper when adding wood.
  This allows more air into the stove. More air helps
  the wood burn properly and prevents pollutants
  from being drawn back into the house instead of
  going  up the  chimney.  Visible smoke or  a.
  constant smoky odor inside the home when using
  a woodburning stove is a sign that the stove is
  not working properly. Soot on furniture in the
  rooms where you are using the  stove also tells
  this. Smoke and soot are signs that the stove is
  releasing pollutants into the indoor air.

Correct Use
• Read  and  follow the instructions  for all
  appliances so you understand how they
  work. Keep the owner's manual in a convenient
  place to refer to when needed.  Also, read and
  follow the warning labels because they tell you
  important safety information that you need to
  know. Reading and following the instructions and
  warning labels could save your life.

CAUTION: Risk of indoor
air pollution.  Use this
heater only in a well
ventilated area. See
operating instructions for
                     CAUTION: Improper fuel may cause
                     pollution and sooting of the burner.
                     Use only water clear No. 1-K kerosene.

                     DANGER: Risk of explosion. Never use
                     gasoline in this heater.
 Always use  the  correct  fuel  for  the
 • Only use water-clear ASTM 1-K kerosene
   for kerosene heaters. The  use of kerosene
   other than 1-K could lead to a release of more
   pollutants in your home. Never use gasoline in
   a kerosene heater because it can cause a fire
   or an explosion. Using even small amounts of
   gasoline could cause a fire.
 • Use seasoned hardwoods (elm, maple, oak)
   instead of softwoods (cedar,  fir,  pine) in
   woodburning stoves and fireplaces. Hard-
   woods are better because they burn hotter and
   form less creosote, an oily, black  tar that sticks
   to chimneys and stove pipes. Do  not use green
   or  wet woods as the  primary wood because
   they make  more creosote  and smoke. Never
   burn painted scrap wood or wood treated with
   preservatives, because  they could release
   highly toxic pollutants, such as arsenic or lead.
   Plastics, charcoal, and colored paper such as
   comics, also produce  pollutants. Never  burn
   anything that the stove or fireplace manufac-
   turer  does not recommend.
' Never use a range, oven, or dryer to  heat
 your home. When you misuse gas appliances in
 this way, they can produce fatal amounts of car-
 bon monoxide.  They can produce  high levels of
 nitrogen dioxide,  too.
ป Never use an  unvented combustion heater
 overnight or in a room where you are sleep-
 ing.  Carbon monoxide from combustion heaters
 can reach dangerous levels.

• Never ignore a safety device when it shuts
  off an appliance. It means that something is
  wrong. Read your appliance instructions to find
  out what you should do or have a professional
  check out the problem.                   !
• Never ignore the smell  of fuel. This usually
  indicates that the appliance is not  operating
  properly or is leaking fuel. Leaking fuel will not,
  always be detectible by smell. If you suspect that,
  you have a fuel leak have  it fixed as soon as
  possible. In most cases you should shut off the
  appliance, extinguish any other flames or pilot,
  lights, shut off other appliances in the area, open
  windows and doors, call for help, and leave
  the area.

Inspection and Maintenance
• Have your combustion  appliance regularly
  inspected and  maintained to reduce your
  exposure to pollutants. Appliances that are not
  working properly can release harmful and even
  fatal amounts of pollutants, especially carbon
  monoxide.                               i
• Have  chimneys  and vents inspected when
  installing or changing  vented heating  ap-
  pliances. Some modifications may be required.
  For  example, if a change was made in your
  heating system from oil to natural gas, the flue
  gas produced by the gas  system could be  hot
  enough to melt  accumulated  oil combustion
  debris in the chimney or vent. This debris could
  block the vent forcing pollutants into the house.
  It is important to clean your chimney and vents
  especially when changing heating systems.

What are  the inspection

and maintenance


The best advice is to follow the recommendations
of the manufacturer. The same  combustion  ap-
pliance  may  have different inspection  and
maintenance requirements, depending upon where
you live.

  In general, check the flame in the furnace com-
bustion chamber at the beginning of the heating
season. Natural gas furnaces should have a blue
flame with perhaps only a slight yellow tip. Call
your appliance service representative to adjust the
burner if there is a lot of yellow in the flame, or
call your local utility company for this service. LP
units should have a flame with a bright blue center
that may have a light yellow tip. Pilot lights on gas
water heaters and gas cooking appliances should
also have a blue flame.  Have a trained service
representative adjust the pilot light if it is yellow
or orange.
  Before each heating season, have flues and
chimneys  inspected  and cleaned before  each
heating season for leakage and for blockage by
creosote or debris.  Creosote buildup or leakage
could cause black stains on the outside of the
chimney or flue. These stains  can mean that
pollutants are leaking into the house.
  The chart on the next page shows how and when
to take care of your appliance.

This booklet discussed the types of pollutants that
may be produced  by combustion  appliances,
described how they might affect your health, and
suggested ways you could reduce your exposure to
them. It also explained that proper appliance selec-
tion,  installation,  operation,  inspection,   and
maintenance  are very important in reducing ex-
posure to combustion pollutants.

Gas Hot Air
Heating System

Heating Systems
and Water

Space Heaters


Air Filters -
Look at flues
for rust and
soot - Yearly

Look at flues
for rust and
soot - Yearly

Look to see
that mantle is
properly seated -
Daily when
in use
Look to see
that fuel tank
is free of water
or other
contaminants -
Daily or before
Look at flues
for rust and
soot - Yearly

Clean/change filter -
As needed
Qualified person check/
clean chimney, clean
combustion chamber,
adjust burners, check
heat exchanger
and operation
Yearly (at start of
heating season)
Qualified person check/
clean chimney, clean
combustion chamber,
adjust burners,
check operation
Yearly (at start of
heating season)
Check and replace wick
Yearly (at start of
heating season)

Clean combustion
Yearly (at start of
heating season)
Drain fuel tank
Yearly (at end of
heating season)
Qualified person
check/clean chimney,
check seams
and gaskets,
check operation
Yearly (at start of
heating season)

For more information:
For a copy of CPSC's booklets What You Should
Know About Space Heaters and What You Should
Know About Kerosene Heaters, and for information
on asbestos, biological pollutants, lead, methylene
chloride, humidifiers, and formaldehyde in your
home, write to:
  U.S. Consumer Product Safety Commission
  Washington, D.C. 20207

For a copy of The Inside Story: A Guide to Indoor
Air Quality, and additional information on indoor
air quality write:
  Public Information Center (PM-211B)
  U.S. Environmental Protection Agency
  401 M Street, SW
  Washington, D.C. 20460

Information on indoor air quality is also available
from local  American  Lung Association  (ALA)
offices. They are listed  in the white pages of the
phone book.

For information on woodstoves write:
  Wood Heater Program (EN-341W)
  U.S. Environmental Protection Agency
  401 M Street, SW
  Washington, DC 20460

For information on kerosene heaters, write or call:
  National Kerosene Heater Association
  3100 West End Avenue, Suite 250
  Nashville, TN 37203
  (Telephone: 615-269-9015)

For information on gas heating appliances, write:
  Gas Appliance Manufacturers Association, Inc.
  1901 North Moore Street, Suite 1100
  Arlington, VA 22209

  American Gas Association
  1515 Wilson Blvd.
  Arlington, VA 22209

For a copy of Straight Answers to Burning Ques-
tions or other woodburning information, write:
  Wood  Heating Alliance
  1101 Connecticut Ave N.W., Suite 700
  Washington, DC 20036
Note: The CPSC and the EPA have not reviewed or approved
all the information and documents on indoor air quality that
may be provided by other groups or organizations.

This document may be reproduced without change, in whole
or in part, without permission, except for use as advertising
material or product endorsement. Any such reproduction
should credit the American Lung Association, the U.S. Con-
sumer Product Safety Commission, and the U.S. Environmental
Protection Agency. The use of all or any part of this document
in a deceptive manner or for purposes of endorsing a particular
product may be subject to appropriate legal action.

U.S. Consumer Product Safety Commission
        Washington, D.C. 20207
 U.S. Environmental Protection Agency
        Washington, D.C. 20460
               The Christmas Seal People •
Contact your local American Lung Association
for more information.