Morbidity A statistical measure of number of
fractions of indicators of illness.
Mortality A statistical measure of number or
fraction of deaths.
National Ambient Air Quality Standards NAAQS, established under the US
Clean Air Act to protect health and welfare.
Nitrogen oxides NO x , a mixture of NO and NO 2
produced in high-temperature combustion processes. Regulated as a Criteria Air Pollutant or
Common Air Pollutant.
Ozone O 3 , a molecule with three atoms of oxygen. It is highly reactive with other chemicals
and biological systems. It is regulated as a
Criteria Air Pollutant or Common Air Pollutant.
Particulate matter Airborne solid material,
unspecified as to chemical composition, regulated as a Criteria Pollutant or Common Air
Pollutant.
Particulate matter, 10 mm PM 10 , airborne particulate material included in sampled air size fraction with aerodynamic size of 10 mm and less.
Particulate matter, 2.5 mm PM 2.5 , particulate
material included in sampled air size fraction
with an aerodynamic size of 2.5 mm or less.
Primary standards or guidelines Air Quality
Standards or Guidelines for Criteria or Common Pollutants set to protect public health.
Risk The probability of an adverse health outcome associated with exposure to a hazardous
material for a defined period of time and exposure level. Usually expressed as a level of
adverse effect, morbidity, or mortality, over
and above background.
Risk assessment The analytical process of evaluating exposure and the hazard potential of a
material to estimate risk.
Secondary standards or guidelines Air Quality
Standards or Guidelines for Criteria or Common Air Pollutants set to protect public welfare
such as visibility or effects on plants.
Standards Regulations that are legally binding.
Stationary sources Fixed sources of air pollution emissions such as power plants.
Sulfur dioxide SO 2 , released from combustion
of sulfur-containing fossil fuels. It is regulated
as a Criteria Air Pollutant or Common Air
Pollutant.
Definition of the Subject
Air quality is the state of the atmosphere in which
humankind lives and works. The air consists of a
complex mixture of gases and suspended droplets
and particles. Some of the gases, such as oxygen
and carbon dioxide, within rather tight concentration limits, are essential for sustaining the life of all
living things. Some of the gases and aerosol particles and droplets, when certain concentrations are
exceeded and with sufficient duration of exposure,
may have adverse effects on humans and other
living things, including vegetation. Various governmental agencies around the world have developed air quality guidelines and standards for
ambient or outdoor air quality. These guidelines
or standards, when achieved or attained, are
intended to be protective of human health and
minimize the potential for other effects such as
impacts on visibility or plants. Some government
entities and statutes characterize the guidelines as
goals to be attained, while other government entities and statutes treat them as rigid standards which
are legally enforced. Guidelines or standards, when
attained, are intended to improve the quality and
sustainability of human life.
Introduction
The quality of the air that people live in and
breathe has no doubt been of concern to people
since early in the evolution of humans. This concern, which must have preceded recorded history,
likely coincided with man’s use of purposeful
combustion, fire, for cooking and heating and
ultimately, for manufacturing and other activities,
including transportation. There is abundant evidence that early humans found it convenient to
live in caves both for shelter and safety. The poor
quality of the air is apparent from the residual soot
coating the interior of caves used as dwellings.
Indeed, pictographs of the interior of the caves
provide documentation of aspects of the life of
those early cave dwellers. As community life
evolved, people continued to live and use fire for
both cooking and heating in poorly ventilated
dwellings.
8
Air Quality Guidelines and Standards
fractions of indicators of illness.
Mortality A statistical measure of number or
fraction of deaths.
National Ambient Air Quality Standards NAAQS, established under the US
Clean Air Act to protect health and welfare.
Nitrogen oxides NO x , a mixture of NO and NO 2
produced in high-temperature combustion processes. Regulated as a Criteria Air Pollutant or
Common Air Pollutant.
Ozone O 3 , a molecule with three atoms of oxygen. It is highly reactive with other chemicals
and biological systems. It is regulated as a
Criteria Air Pollutant or Common Air Pollutant.
Particulate matter Airborne solid material,
unspecified as to chemical composition, regulated as a Criteria Pollutant or Common Air
Pollutant.
Particulate matter, 10 mm PM 10 , airborne particulate material included in sampled air size fraction with aerodynamic size of 10 mm and less.
Particulate matter, 2.5 mm PM 2.5 , particulate
material included in sampled air size fraction
with an aerodynamic size of 2.5 mm or less.
Primary standards or guidelines Air Quality
Standards or Guidelines for Criteria or Common Pollutants set to protect public health.
Risk The probability of an adverse health outcome associated with exposure to a hazardous
material for a defined period of time and exposure level. Usually expressed as a level of
adverse effect, morbidity, or mortality, over
and above background.
Risk assessment The analytical process of evaluating exposure and the hazard potential of a
material to estimate risk.
Secondary standards or guidelines Air Quality
Standards or Guidelines for Criteria or Common Air Pollutants set to protect public welfare
such as visibility or effects on plants.
Standards Regulations that are legally binding.
Stationary sources Fixed sources of air pollution emissions such as power plants.
Sulfur dioxide SO 2 , released from combustion
of sulfur-containing fossil fuels. It is regulated
as a Criteria Air Pollutant or Common Air
Pollutant.
Definition of the Subject
Air quality is the state of the atmosphere in which
humankind lives and works. The air consists of a
complex mixture of gases and suspended droplets
and particles. Some of the gases, such as oxygen
and carbon dioxide, within rather tight concentration limits, are essential for sustaining the life of all
living things. Some of the gases and aerosol particles and droplets, when certain concentrations are
exceeded and with sufficient duration of exposure,
may have adverse effects on humans and other
living things, including vegetation. Various governmental agencies around the world have developed air quality guidelines and standards for
ambient or outdoor air quality. These guidelines
or standards, when achieved or attained, are
intended to be protective of human health and
minimize the potential for other effects such as
impacts on visibility or plants. Some government
entities and statutes characterize the guidelines as
goals to be attained, while other government entities and statutes treat them as rigid standards which
are legally enforced. Guidelines or standards, when
attained, are intended to improve the quality and
sustainability of human life.
Introduction
The quality of the air that people live in and
breathe has no doubt been of concern to people
since early in the evolution of humans. This concern, which must have preceded recorded history,
likely coincided with man’s use of purposeful
combustion, fire, for cooking and heating and
ultimately, for manufacturing and other activities,
including transportation. There is abundant evidence that early humans found it convenient to
live in caves both for shelter and safety. The poor
quality of the air is apparent from the residual soot
coating the interior of caves used as dwellings.
Indeed, pictographs of the interior of the caves
provide documentation of aspects of the life of
those early cave dwellers. As community life
evolved, people continued to live and use fire for
both cooking and heating in poorly ventilated
dwellings.
8
Air Quality Guidelines and Standards