The following glossary explains terms relating to air quality that you will find throughout this site.
A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z
Air NEPM
National Environment Protection Measure for Ambient Air Quality
air pollutant
a chemical which reduces the quality of air
includes ozone, carbon monoxide, sulfur dioxide, nitrogen dioxide and air particles, which are monitored by DECCW and used in the AQI
air pollution
the emission into the air of any impurity including odours
air quality index (AQI)
a value derived from air quality data readings, which allows for more meaningful comparison of pollutants affecting air quality. The index is derived using the following formula:
AQI
see air quality index
airshed
a volume of air confined to a geographic region and within which pollutants are contained
an area in which air quality is subject to common influences from emissions, meteorology and topography
air toxics
a class of pollutants including polycyclic aromatic hydrocarbons (PAHs), heavy metals and aldehydes, as well as VOCs
ambient air
the external air environment (does not include the air environment inside buildings or structures)
anthropogenic
human-made or related to human activity
benzene
a type of VOC
known to cause cancer and has no safe level of exposure
biodiesel
a type of biofuel made from oilseed crops, recycled cooking oil or waste animal fat
available at some service stations in NSW
biogenic
of natural origin
biomass
plant materials and animal waste used as fuel
the total mass of living matter in a given area
carbon
an element which is the basis of all organic compounds or substances
often used to broadly refer to all greenhouse gases
carbon footprint
a measure of the greenhouse gas emissions that can be attributed to an activity, an individual, a household or a business
carbon dioxide (CO2)
a naturally occurring gas that's also a by-product of burning fossil fuels and biomass, other industrial processes and land-use changes
the principal anthropogenic greenhouse gas that affects the earth's temperature
carbon monoxide (CO)
an odourless, colourless gas produced by incomplete oxidation (burning)
natural sources: wildfires, oxidation in the oceans and air of methane produced from organic decomposition
human-made sources: the motor vehicle is by far the largest human source although any combustion process can produce it
enters the bloodstream through the lungs and prevents the normal transport of oxygen by blood to reduce the amount of oxygen reaching the body's organs and tissues, especially the heart
people suffering from heart disease are most at risk; they may experience chest pain if they are exposed to carbon monoxide, particularly while exercising
carbon neutral
describes an activity which produces zero net carbon emissions
carbon offset
represent reductions in greenhouse gases relative to a business-as-usual baseline
are tradeable and often used to negate (or offset) all or part of another entity's emissions
carcinogen
a cancer-causing substance
climate change
a change of climate that is attributed directly or indirectly to human activity which alters the composition of the global atmosphere and that is in addition to natural climate variability over comparable time periods (UNFCCC)
CSIRO
Commonwealth Scientific and Independent Research Organisation
OEH
Office of Environment and Heritage
emissions
the release of gases into the atmosphere
exceedence
an instance where a goal or standard for a particular pollutant is exceeded
extreme pollution events
infrequent events like bushfires and dust storms which generate extreme levels of air pollution. It is anticipated that the frequency of these will continue to rise as drought conditions continue due to climate change
fossil fuels
coal, oil or gas
GHGs
see greenhouse gases
global warming
a rise in the Earth's overall temperature caused by an increase in heat-retaining gases in the atmosphere
GMR
see greater metropolitan region
goal
see standard
greater metropolitan region
includes Sydney, the Lower Hunter and Illawarra regions
home to around 70% of the NSW population
view map of the Greater Metropolitan Region (GMR)
greenhouse effect
the trapping of heat by naturally occurring heat-retaining atmospheric gases (water vapour, carbon dioxide, nitrous oxide, methane and ozone) that keeps the earth about 30°C (60°F) warmer than if these gases did not exist
greenhouse gases (GHGs)
gases that cause global warming and climate change
the major GHGs are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs) and sulfur hexafluoride (SF6)
ground-level ozone
a colourless, gaseous secondary pollutant which can form at ground-level when VOCs react with NOx in warm, sunny conditions
one of the key chemicals in photochemical smog and is often used as a measure of it
breathing ozone can affect lung function and worsen asthma
health alerts
issued at 4 pm if the AQI is likely to be above 100 the next day, a level at which people sensitive to the effects of air pollution are likely to feel its impacts
Kyoto Protocol
an international treaty negotiated under the auspices of the UNFCCC entered into force in 2005
sets, among other things, binding targets for the reduction of greenhouse gas emissions by individual developed countries to be met within the first commitment period of 2008-12
lead
exposure can affect intellectual development in children
prohibition of the sale of leaded petrol since 2002 has eliminated the major source of lead in ambient air
load-based fees
licence fees that are based on the amount of particular pollutants that are discharged by an activity
do not apply to all activities
micrometers (µm)
a unit of length equal to one thousandth of a millimetre or one millionth of a meter
nitrogen oxide (NO)
measured at certain monitoring sites, but not used in reporting the air quality index (AQI)
nitrogen dioxide (NO2)
a respiratory irritant which can make existing respiratory illness symptoms worse
makes people with asthma more susceptible to lung infections and asthma triggers like pollen and exercise
nitrogen dioxide levels can be high near busy roads and also indoors when unflued gas appliances are used
NOx
oxides of nitrogen; includes nitrogen oxide (NO) and nitrogen dioxide (NO2); an ozone precursor
oxides of nitrogen
see NOx
ozone (O3)
occurs in the stratosphere to protect the earth against the sun's damaging UV rays
a colourless, gaseous secondary pollutant which can form at ground-level when VOCs react with NOx in warm, sunny conditions
one of the key chemicals in photochemical smog and is often used as a measure of it
breathing ozone can affect lung function and worsen asthma
ozone layer
absorbs most of the harmful ultraviolet B (UV-B) radiation from the sun, which can cause skin cancer, cataracts, suppression of the immune system, etc. and damage to agricultural crops, livestock, and industrial and domestic materials.
particles
solid or liquid particles that are suspended in the air and adversely impact health
the size of a particle determines its potential impact on human health: larger particles are usually trapped in the nose and throat and swallowed; smaller particles may reach the lungs and cause irritation there
particulates
see particles
photochemical
relating to the chemical reaction of light, including sunlight
PM
particulate matter
PM10
particles less than or equal to 10 micrometers (µm) in diameter
PM2.5
particles less than or equal to 2.5 micrometers (µm) in diameter
pollutant
a contaminating substance
precursor
a chemical that is required for another compound to form, as in the course of a chemical reaction
e.g. VOCs and NOx are ozone precursors, where they need to first be present to then react with each other to form ozone
primary pollutant
emitted directly from a source
radon
an inert gas produced when elements in soil and rocks decay
its decay produces alpha particles which damage lung tissue when inhaled
classified as a class 1 carcinogen
RTA
NSW Roads and Traffic Authority
secondary pollutant
formed by the reactions of other pollutants
smog
a complex mixture of chemicals - mainly ozone and nitrogen dioxide - which appears as a white haze in urban areas during warm, sunny conditions
SO2
see sulfur dioxide
solvent
a substance used to dissolve another substance, for example bleach and methylated spirits
standard
the standards for ozone, carbon monoxide, sulfur dioxide, nitrogen dioxide and air particles were set in 1998 by the National Environment Protection Council
the standard for visibility is set by NSW
stratosphere
the second major layer of the Earth's atmosphere
contains the ozone layer
sulfur dioxide (SO2)
the main human-made sources are the smelting of mineral ores containing sulfur and the combustion of fossil fuels
a respiratory irritant which can worsen existing respiratory illness
total suspended particulates (TSP)
a combination of large and small particles in the atmosphere which can reach high concentrations when there is no wind to scatter them
toxic
poisonous
UNFCCC
United Nations Framework Convention on Climate Change
unflued
not externally vented
VOCs
volatile and semi-volatile organic compounds (mainly hydrocarbons)
an ozone precursor
volatile organic compounds
see VOCs
The following glossary explains terms relating to air quality that you will find throughout this site.
A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z
Air NEPM
National Environment Protection Measure for Ambient Air Quality
air pollutant
a chemical which reduces the quality of air
includes ozone, carbon monoxide, sulfur dioxide, nitrogen dioxide and air particles, which are monitored by DECCW and used in the AQI
air pollution
the emission into the air of any impurity including odours
air quality index (AQI)
a value derived from air quality data readings, which allows for more meaningful comparison of pollutants affecting air quality. The index is derived using the following formula:
AQI
see air quality index
airshed
a volume of air confined to a geographic region and within which pollutants are contained
an area in which air quality is subject to common influences from emissions, meteorology and topography
air toxics
a class of pollutants including polycyclic aromatic hydrocarbons (PAHs), heavy metals and aldehydes, as well as VOCs
ambient air
the external air environment (does not include the air environment inside buildings or structures)
anthropogenic
human-made or related to human activity
benzene
a type of VOC
known to cause cancer and has no safe level of exposure
biodiesel
a type of biofuel made from oilseed crops, recycled cooking oil or waste animal fat
available at some service stations in NSW
biogenic
of natural origin
biomass
plant materials and animal waste used as fuel
the total mass of living matter in a given area
carbon
an element which is the basis of all organic compounds or substances
often used to broadly refer to all greenhouse gases
carbon footprint
a measure of the greenhouse gas emissions that can be attributed to an activity, an individual, a household or a business
carbon dioxide (CO2)
a naturally occurring gas that's also a by-product of burning fossil fuels and biomass, other industrial processes and land-use changes
the principal anthropogenic greenhouse gas that affects the earth's temperature
carbon monoxide (CO)
an odourless, colourless gas produced by incomplete oxidation (burning)
natural sources: wildfires, oxidation in the oceans and air of methane produced from organic decomposition
human-made sources: the motor vehicle is by far the largest human source although any combustion process can produce it
enters the bloodstream through the lungs and prevents the normal transport of oxygen by blood to reduce the amount of oxygen reaching the body's organs and tissues, especially the heart
people suffering from heart disease are most at risk; they may experience chest pain if they are exposed to carbon monoxide, particularly while exercising
carbon neutral
describes an activity which produces zero net carbon emissions
carbon offset
represent reductions in greenhouse gases relative to a business-as-usual baseline
are tradeable and often used to negate (or offset) all or part of another entity's emissions
carcinogen
a cancer-causing substance
climate change
a change of climate that is attributed directly or indirectly to human activity which alters the composition of the global atmosphere and that is in addition to natural climate variability over comparable time periods (UNFCCC)
CSIRO
Commonwealth Scientific and Independent Research Organisation
OEH
Office of Environment and Heritage
emissions
the release of gases into the atmosphere
exceedence
an instance where a goal or standard for a particular pollutant is exceeded
extreme pollution events
infrequent events like bushfires and dust storms which generate extreme levels of air pollution. It is anticipated that the frequency of these will continue to rise as drought conditions continue due to climate change
fossil fuels
coal, oil or gas
GHGs
see greenhouse gases
global warming
a rise in the Earth's overall temperature caused by an increase in heat-retaining gases in the atmosphere
GMR
see greater metropolitan region
goal
see standard
greater metropolitan region
includes Sydney, the Lower Hunter and Illawarra regions
home to around 70% of the NSW population
view map of the Greater Metropolitan Region (GMR)
greenhouse effect
the trapping of heat by naturally occurring heat-retaining atmospheric gases (water vapour, carbon dioxide, nitrous oxide, methane and ozone) that keeps the earth about 30°C (60°F) warmer than if these gases did not exist
greenhouse gases (GHGs)
gases that cause global warming and climate change
the major GHGs are carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs) and sulfur hexafluoride (SF6)
ground-level ozone
a colourless, gaseous secondary pollutant which can form at ground-level when VOCs react with NOx in warm, sunny conditions
one of the key chemicals in photochemical smog and is often used as a measure of it
breathing ozone can affect lung function and worsen asthma
health alerts
issued at 4 pm if the AQI is likely to be above 100 the next day, a level at which people sensitive to the effects of air pollution are likely to feel its impacts
Kyoto Protocol
an international treaty negotiated under the auspices of the UNFCCC entered into force in 2005
sets, among other things, binding targets for the reduction of greenhouse gas emissions by individual developed countries to be met within the first commitment period of 2008-12
lead
exposure can affect intellectual development in children
prohibition of the sale of leaded petrol since 2002 has eliminated the major source of lead in ambient air
load-based fees
licence fees that are based on the amount of particular pollutants that are discharged by an activity
do not apply to all activities
micrometers (µm)
a unit of length equal to one thousandth of a millimetre or one millionth of a meter
nitrogen oxide (NO)
measured at certain monitoring sites, but not used in reporting the air quality index (AQI)
nitrogen dioxide (NO2)
a respiratory irritant which can make existing respiratory illness symptoms worse
makes people with asthma more susceptible to lung infections and asthma triggers like pollen and exercise
nitrogen dioxide levels can be high near busy roads and also indoors when unflued gas appliances are used
NOx
oxides of nitrogen; includes nitrogen oxide (NO) and nitrogen dioxide (NO2); an ozone precursor
oxides of nitrogen
see NOx
ozone (O3)
occurs in the stratosphere to protect the earth against the sun's damaging UV rays
a colourless, gaseous secondary pollutant which can form at ground-level when VOCs react with NOx in warm, sunny conditions
one of the key chemicals in photochemical smog and is often used as a measure of it
breathing ozone can affect lung function and worsen asthma
ozone layer
absorbs most of the harmful ultraviolet B (UV-B) radiation from the sun, which can cause skin cancer, cataracts, suppression of the immune system, etc. and damage to agricultural crops, livestock, and industrial and domestic materials.
particles
solid or liquid particles that are suspended in the air and adversely impact health
the size of a particle determines its potential impact on human health: larger particles are usually trapped in the nose and throat and swallowed; smaller particles may reach the lungs and cause irritation there
particulates
see particles
photochemical
relating to the chemical reaction of light, including sunlight
PM
particulate matter
PM10
particles less than or equal to 10 micrometers (µm) in diameter
PM2.5
particles less than or equal to 2.5 micrometers (µm) in diameter
pollutant
a contaminating substance
precursor
a chemical that is required for another compound to form, as in the course of a chemical reaction
e.g. VOCs and NOx are ozone precursors, where they need to first be present to then react with each other to form ozone
primary pollutant
emitted directly from a source
radon
an inert gas produced when elements in soil and rocks decay
its decay produces alpha particles which damage lung tissue when inhaled
classified as a class 1 carcinogen
RTA
NSW Roads and Traffic Authority
secondary pollutant
formed by the reactions of other pollutants
smog
a complex mixture of chemicals - mainly ozone and nitrogen dioxide - which appears as a white haze in urban areas during warm, sunny conditions
SO2
see sulfur dioxide
solvent
a substance used to dissolve another substance, for example bleach and methylated spirits
standard
the standards for ozone, carbon monoxide, sulfur dioxide, nitrogen dioxide and air particles were set in 1998 by the National Environment Protection Council
the standard for visibility is set by NSW
stratosphere
the second major layer of the Earth's atmosphere
contains the ozone layer
sulfur dioxide (SO2)
the main human-made sources are the smelting of mineral ores containing sulfur and the combustion of fossil fuels
a respiratory irritant which can worsen existing respiratory illness
total suspended particulates (TSP)
a combination of large and small particles in the atmosphere which can reach high concentrations when there is no wind to scatter them
toxic
poisonous
UNFCCC
United Nations Framework Convention on Climate Change
unflued
not externally vented
VOCs
volatile and semi-volatile organic compounds (mainly hydrocarbons)
an ozone precursor
volatile organic compounds
see VOCs