A |
|
Abatement |
the reduction in degree or intensity, or
elimination, of pollution |
Acid Deposition |
a term for the conversion of sulfur oxide
and nitrogen oxide emissions into acidic compounds which
precipitate in rain, snow, fog, or dry particles |
Acute |
occurring over a short period of time;
used to describe brief exposures and effects which appear
promptly after exposure |
Adverse Health Effects |
health effects from exposure to air contaminants
that may range from relatively mild temporary conditions,
such as minor eye or throat irritation, shortness of breath,
or headaches, to permanent and serious conditions such
as birth defects, cancer, or damage to lungs, nerves,
liver, heart, or other organs |
Aerosol |
particle of solid or liquid matter that
can remain suspended in the air because of its small size
(generally under one micron) |
Afterburner |
an air pollution abatement device that
removes undesirable organic gases through incineration |
Air |
so-called "pure" air is a mixture
of gases containing about 78 percent nitrogen; 21 percent
oxygen; less than 1 percent of carbon dioxide, argon,
and other inert gases; and varying amounts of water vapor |
Air Basins |
areas defined by geographical or administrative boundaries;
used for air pollution control programs |
Air Monitoring |
sampling for and measuring of pollutants present in the atmosphere |
Air Pollution |
the presence of polluting gases and suspended particles
in the atmosphere in excess of air quality standards |
Air Quality Criteria |
the varying amounts of pollution and lengths
of exposure at which specific adverse effects to health
and comfort take place |
Air Quality Plan (AQP) |
a plan developed to attain and maintain an air quality standard |
Air Quality Management District (AQMD) |
local agency charged with controlling air pollution
and attaining air quality standards. The Bay Area Air
Quality Management District is the regional AQMD that
includes all of seven counties (Alameda, Contra Costa,
Marin, Napa, San Francisco, San Mateo and Santa Clara)
and the southern halves of Solano and Sonoma counties |
Air Quality Standard (AQS) |
the prescribed level of a pollutant in the outside
air that should not be exceeded during a specific time
period to protect public health. Established by both federal
and state governments |
Airshed |
a term denoting a geographical area of which, because
of topography, meteorology, and climate, shares the same
air (see Air Basins) |
Ambient Air |
outside air; any portion of the atmosphere not confined
by walls and a roof |
Aromatic |
a hydrocarbon that consists of one or more benzenoid
rings (i. e., benzene) |
Asbestos |
a mineral fiber that can pollute air or water and cause
cancer or asbestosis when inhaled. EPA has banned or severely
restricted its use in manufacturing and construction |
Association of Bay Area Governments (ABAG) |
a voluntary joint-powers comprehensive regional planning
agency for the cities and counties of the Bay Area |
Asthma |
a medical condition characterized by abnormal restriction
of breathing, especially in response to allergens or air
contaminants |
Atmosphere |
the layer of life-supporting gases (air) that surrounds
the earth |
Attainment |
a designation used when an area meets an air quality
standard |
Attrition Fire |
A fire whose fuel is comprised of dead or prunned tree
or bush branches, limbs and cuttings. |
Authority to Construct (A/C) |
a pre-construction permit issued by the District |
B |
|
Baghouse |
an air pollution abatement device that traps particulates
(dust) by forcing gas streams through large permeable
bags usually made of glass fibers |
Banking |
a provision in District permit regulations that allows
a facility to obtain credits for reducing emissions beyond
regulatory limits and use those credits at a later date,
similar to how a savings account works |
Bay Area '94 Clean Air Plan |
the planning document produced by the District identifying
all feasible measures for the reduction of ground-level
ozone in the Bay Area as mandated by the California Clean
Air Act |
Best Available Control Technology (BACT) |
an emission limitation based on using the most up-to-date
methods, systems, techniques, and production processes
available to achieve the greatest feasible emission reductions.
These are the most stringent requirements for new or modified
sources and are determined on a case-by-case basis as
part of New Source Review |
Best Available Retrofit Control Technology (BARCT) |
an emission limitation based on the maximum degree of
reduction achievable for existing sources taking into
account environmental, energy, and economic impact |
Bi-fuel |
a vehicle that has the ability to operate on gasoline
or diesel as their primary fuel. These types of
vehicles are NOT eligible for Air District funding |
Biodiesel |
Biodiesel is a cleaner-burning
diesel replacement fuel made from natural, renewable sources
such as new and used vegetable oils and animal fats. Like
petroleum diesel, biodiesel operates in compression-ignition
engines. Blends of up to 20% biodiesel (mixed with petroleum
diesel fuels) can be used in nearly all diesel equipment
and are compatible with most storage and distribution
equipment. These low level blends (20% and less) don't
require any engine modifications and can provide the same
payload capacity as diesel. Using biodiesel in a conventional
diesel engine substantially reduces emissions |
British Thermal Unit (BTU) |
a unit of heat used to describe the capacity of boilers
and furnaces. One BTU equals the amount of heat required
to raise the temperature of one pound of water one degree
Farenheit at sea level |
C |
|
California Air Resources Board (CARB) |
the state of California agency responsible for air pollution control |
California Clean Air Act (CCAA) |
legislation enacted in 1988, and amended in 1992 and
1996, mandating a planning process to attain state ambient
air quality standards |
Cal-EPA |
the state agency created in 1991 to oversee the various
state environmental agencies |
Carbon Dioxide (CO2) |
a colorless, odorless, non-poisonous gas that results
from fossil fuel combustion and is a normal constituent
of ambient air |
Carbon Monoxide (CO) |
a colorless, odorless, toxic gas produced by the incomplete
combustion of carbon-containing substances. One of the
major air pollutants, it is emitted in large quantities
by exhaust from gasoline-powered vehicles |
Carcinogen |
any substance that can cause or contribute to the production
of cancer |
Catalytic Converter |
an air pollution abatement device used primarily on
motor vehicles and other sources. It removes organic contaminants
by oxidizing them into carbon dioxide and water through
chemical reaction. May convert nitrogen dioxide to nitrogen
and oxygen or promote other similar reactions |
Chlorofluorocarbons (CFCs) |
a family of inert, nontoxic, and easily liquified chemicals
used in refrigeration, air conditioning, packaging, insulation,
or as solvents and aerosol propellants. Because CFCs are
not destroyed in the lower atmosphere they drift into
the upper atmosphere where their chlorine components destroy
the ozone layer |
Chronic |
marked by long duration or frequent recurrence, as with
a chronic disease |
Clean Air Act (CAA) |
long standing federal legislation that is the legal
basis for the national clean air programs, last amended
in 1990 |
Clean Air Vehicle |
a vehicle that does not use gasoline or diesel as its
primary fuel and is certified by CARB to meet very stringent
tailpipe emission standards |
Coefficient of Haze (COH) |
a measurement of the quantity of dust and smoke in the
atmosphere in a theoretical 1000 linear feet of air. A
COH of less than 1 is considered clean air and more than
3 is considered dirty air |
Combustion |
burning, that is, the production of heat and light energy
through chemical change, such as the oxidation of hydrocarbon
fuel |
Continuous Emission Monitor (CEM) |
a type of air emission monitoring device installed to
operate continuously inside of a smoke stack or other
emission source |
Criteria Air Pollutants |
as required by the Clean Air Act, the EPA identifies
and set standards to protect human health and welfare
for six pollutants: ozone, carbon monoxide, particulate
matter (PM10), sulfur dioxide, lead, and nitrogen oxide.
The term "criteria pollutants" derives from
the requirement that the EPA must describe the characteristics
and potential health and welfare effects of these pollutants.
EPA periodically reviews new scientific data and may propose
revisions to the standards as a result |
Cyclone |
an air pollution abatement device that removes heavy
particles from an air stream through centrifugal force |
D |
|
Degreaser |
equipment which removes grease, dirt or unwanted materials
from any part or product. Degreasers typically use solvents,
as liquid baths or condensing vapors, to remove such material |
Dew Point |
the temperature at which droplets of water condense
from air (dependent on the prevailing humidity) |
Diesel Engine |
a type of internal-combustion engine that uses low-volatility
petroleum fuel and fuel injectors and initiates combustion
using compression ignition (as opposed to spark ignition,
which is used with gasoline engines.) |
Dual-fuel |
Engines that operate on a combination of natural gas
and diesel fuel |
Dust |
solid particulate matter that can become airborne |
E |
|
Ecology |
the interrelationship of organisms and their environment
and the science that is concerned with that interrelationship |
Electrostatic Precipitator |
an air pollution abatement device that removes particulate
matter from a gas stream by imparting an electrical charge
to the particles for mechanical collection on an electrode |
Emission Factor |
the relationship between the amount of pollution produced
and the amount of raw material processed or burned. For
example, the emission factor for oxides of nitrogen from
fuel oil combustion in an industrial boiler would be the
number of pounds of oxides of nitrogen emitted per 1000
gallons of fuel oil burned. By using the emission factor
of a pollutant and specific data regarding quantities
of material used by a given source, it is possible to
compute emissions for the source. This approach is used
in preparing an emissions inventory |
Emission lnventory |
a list of air pollutants emitted into a community's
atmosphere, in amounts (commonly tons) per day or year,
by type of source |
Emission Standard |
the maximum amount of pollution that is permitted to
be discharged from a polluting source - for example, the
number of pounds of dust that may be emitted per hour
from an industrial process |
Emulsified diesel |
This is diesel that is
mixed with a small percentage of water and an agent that
keeps the water and diesel mixed. By adding the water
to the diesel a smaller amount emissions are created when
the fuel is burned |
Environment |
the aggregate of all the external conditions and influences
affecting the life, development, and ultimately the survival
of an organism. More commonly, the earth's crust, water
resources, life forms, and atmosphere |
Environmental Protection Agency (EPA) |
the federal agency responsible for control of air and
water pollution, toxic substances, solid waste, and cleanup
of contaminated sites |
Equivalent Opacity |
the application of the Ringelmann system to the evaluation
of the density of other than black smoke (see Ringelmann) |
Ethanol |
ethyl alcohol, a volatile alcohol containing two carbons
(CH3CH2OH). For fuel use, it would be produced by fermentation
of corn or other plant products. away |
Evaporation |
the physical transformation of a liquid to a gas at
any temperature below its boiling point |
Exceedance |
a measured level of an air pollutant higher than the
national or state ambient air quality standard |
F |
|
Flexible Fuel Vehicle |
vehicles that can use either
alcohol fuels (methanol or ethanol) or a combination of
alcohol fuel and unleaded gasoline |
Fluorocarbon |
an organic compound that contains
fluorine. Some of these compounds may affect health but
they are non-reactive and therefore not smog forming |
Fossil Fuels |
coal, oil, and natural gas; so-called
because they are the remains of ancient plant and animal
life |
Fume |
solid particles under 1 micron
in diameter, formed as vapors condense or as chemical
reactions take place |
Furnace |
a combustion chamber; an enclosed
structure in which fuel is burned to heat air or material |
G |
|
Greenhouse Effect |
the warming of the earth's
atmosphere caused by a buildup of carbon dioxide and other
trace gases. This buildup allows light from the sun's
rays to heat the earth but prevents a counterbalancing
loss of heat |
Ground Level Monitor (GLM) |
a type of air pollution monitoring
device located around major industrial facilities to measure
ambient levels of certain pollutants |
H |
|
Halogen |
a family of chemical elements
that includes fluorine, chlorine, bromine, and iodine |
Halogenated Organic Compounds |
organic compounds containing
one or more atoms of a halogen. These compounds tend to
be stable and non-reactive, and therefore have low smog-producing
potential |
Health Risk |
the probability that exposure
to a given set of toxic air contaminants will result in
an adverse health effect. The health risk is affected
by several factors: the amount and toxicity of emissions;
the weather; how far sources are from people; the distance
between sources; and the age, health and lifestyle of
the people living and working at the receptor location.
The term "risk" usually refers to the increased
chance of contracting cancer as a result of an exposure
and is expressed as a probability, e.g., chances-in-a-million |
Health Risk Assessment |
a document that identifies the
risks and quantities of possible adverse health effects
that may result from exposure to emissions of toxic air
contaminants. A health risk assessment cannot predict
specific health effects; it only describes the increased
possibility of adverse health effects based on the best
scientific information available |
"Hot Spot" |
a location where emissions from
specific sources may expose individuals and population
groups to elevated risks of adverse health effects, including
but not limited to cancer, and contribute to the cumulative
health risks of emissions from other sources in the area |
Hydrocarbon |
any of a vast number of compounds containing carbon
and hydrogen in various combinations; found especially
in fossil fuels. Some of the hydrocarbon compounds are
major air pollutants; they may be active participants
in the photochemical process or affect health |
Hydrogen Sulfide (H2S) |
a gas characterized by a "rotten egg" smell
that is often produced by and found in the vicinity
of oil refineries, chemical plants and sewage treatment
plants |
I |
|
Incineration |
the burning of household
or industrial waste in a combustion chamber |
Inert Gas |
a gas such as helium, neon, or
argon that does not react with other substances under
ordinary conditions |
Inorganic Gaseous Pollutant |
a gaseous pollutant that is not
an organic compound. Examples are: sulfur dioxide, hydrogen
sulfide and nitrogen oxides |
Internal Combustion Engine (ICE) |
an engine in which both the heat energy and the ensuing
mechanical energy are produced inside the engine |
Inversion |
the phenomenon of a layer
of warm air pressing down on cooler air below it. Inversions
are a special problem because they prevent the natural
dispersion and dilution of air contaminants |
L |
|
LAER (lowest achievable emission rate) |
under the Clean Air Act, the rate of emissions that
reflects (a) the most stringent emissions limitation in
the state implementation plan identified for a source
unless the owner or operator demonstrates such limitations
are not achievable or (b) the most stringent emissions
limitation achieved in practice, whichever is more stringent |
M |
|
Maximum Achievable Control
Technology(MACT) |
EPA standards mandated
by the 1990 amendments to the federal Clean Air Act for
the control of toxic emissions from various industries.
Industries range from dry cleaners to petroleum refineries |
Manual of Procedures (MOP) |
a manual of District enforcement,
permitting, source testing, laboratory and monitoring
procedures used by the staff and industry to determine
whether industries are meeting Air District regulations.
Also contains guidelines for environmental processes under
the California Environmental Quality Act (CEQA), and procedures
for calculating and generating mobile source emission
credits |
Major Source |
a source that emits or has the
potential to emit more than 100 tons of any pollutant
regulated under the federal Clean Air Act, more than 10
tons of any hazardous air pollutants or 25 tons of all
hazardous air pollutants |
Methanol |
a single carbon alcohol, generally produced from natural
gas (methane) |
Metropolitan Transportation Commission (MTC) |
the regional agency that provides comprehensive regional
transportation planning for the Bay Area and distributes
federal and state transportation assistance funds |
Micro |
a prefix meaning 1/1,000,000. Abbreviated by the Greek
letter µ |
Micron |
a unit of length equal to one thousandth of a millimeter,
or about 1/25,000 of an inch |
Milli |
a prefix meaning 1/1,000 |
Mist |
liquid particles up to 100 microns in diameter |
Mixing Depth |
the expanse in which air rises from the earth and mixes
with the air above it until it meets air of equal or warmer
temperature |
Mobile Source |
a moving source of air
pollution; includes cars, trucks, motorcycles, and airplanes |
N |
|
National Ambient Air Quality Standards (NAAQS) |
health-based pollutant concentration limits
established by EPA that apply to outside air (see Criteria
Pollutants) |
National Emissions Standards for Hazardous Air Pollutants (NESHAPS) |
emissions standards set by EPA for air
pollutants not covered by NAAQS that may cause an increase
in deaths or in serious, irreversible, or incapacitating
illness; includes. toxic emissions such as benzene |
Natural Gas |
Natural gas
is a mixture of hydrocarbons (mainly methane (CH4)) and
is produced either from gas wells or in conjunction with
crude oil production. Because of the gaseous nature of
this fuel, it must be stored onboard a vehicle in either
a compressed gaseous state (CNG) or in a liquefied state
(LNG) |
New Source Performance Standards (NSPS) |
pollutant emission limits for newly constructed
sources; defined in the BAAQMD's Regulation 10 |
New Source Review (NSR) |
a permitting procedure for new or modified
stationary sources found in the BAAQMD's Regulation 2.
NSR applies if the emissions from the new source are above
a trigger level |
Nitric Oxide (NO) |
precursor of ozone, NO2, and nitrate; usually
emitted from combustion processes. Converted to nitrogen
dioxide (NO2) in the atmosphere, it then becomes involved
in the photochemical process and/or particulate formation |
Nitrogen Oxides (NOx) |
gases formed in great part from atmospheric
nitrogen and oxygen when combustion takes place under
conditions of high temperature and high pressure; considered
a major air pollutant and precursor of ozone |
Nonattainment Area |
defined geographic area that does not meet
one or more of the federal air quality standards for the
criteria pollutants |
O |
|
Open Burning |
the uncontrolled
burning of waste materials in the open, in outdoor incinerators,
or in an open dump, either intentionally or accidentally.
Open burning is regulated in the Bay Area |
Organic Compounds |
a large group of chemical compounds that
contain carbon. All living organisms are made up of organic
compounds. Some types of organic gases, including olefins,
substituted aromatics and aldehydes, are highly reactive
-- i.e., have high ozone-producing potential. Standards
to control organic compounds are found in the BAAQMD's
Regulation 8 |
Oxidant |
an air pollutant containing oxygen that
can react chemically with other substances. Ozone, and
nitrogen compounds are examples of oxidants |
Ozone (O3) |
a pungent, colorless, toxic gas. Close
to the earth's surface it is produced photochemically
from hydrocarbons, oxides of nitrogen and sunlight and
is a major component of smog. At very high altitudes,
it protects the earth from harmful ultraviolet radiation |
Ozone Depletion |
destruction of the stratospheric ozone
layer, which shields the earth from ultraviolet radiation.
This destruction is caused by the breakdown of certain
chlorine and/or bromine-containing compounds (chlorofluorocarbons
or halons) that catalytically destroy ozone molecules
in the stratosphere |
P |
|
Particulate |
a particle of solid
or liquid matter; soot, dust, aerosols, fumes and mists |
Parts Per Million (PPM) |
the number of parts of a given pollutant
in a million parts of air |
Permit to Operate (P/O) |
an operational permit issued yearly by
the District to sources that meet District regulations |
Photochemical Process |
the process by which sunlight acts upon
various compounds, causing a chemical reaction to occur |
Photochemical Smog |
produced when hydrocarbons and oxides of
nitrogen combine in the presence of sunlight to form ozone |
Plume |
a visible or measurable discharge of a
contaminant from a given point of origin that can be measured
according to the Ringelmann scale |
PM2.5 (Particulate Matter less than 2.5
microns) |
tiny solid or liquid particules, generally
soot and aerosols. The size of the particles (2.5 microns
or smaller, about 0.0001 inches or less) allows them to
easily enter the air sacs deep in the lungs where they
may cause adverse health effects; PM2.5 also causes visibility
reduction |
PM10 (Particulate Matter less than 10 microns) |
tiny solid or liquid particles of soot,
dust, smoke, fumes, and aerosols. The size of the particles
(10 microns or smaller, about 0.0004 inches or less) allows
them to easily enter the air sacs in the lungs where they
may be deposited, resulting in adverse health effects.
PM10 also causes visibility reduction and is a criteria
air pollutant |
Pollutant Standards Index (PSI) |
a system developed by the federal government
for reporting air pollution concentrations to the public
as numerical values between 0 and 500 |
Precipitators |
any number of devices using mechanical,
electrical, or chemical means to collect particulates.
Used to measure, analyze, or control particulates |
Precursor |
compounds that change chemically or physically
after being emitted into the air and eventually produce
air pollutants. For example, organic compounds are precursors
for ozone |
Prevention of Significant Deterioration (PSD) |
an EPA program
in which state and/or federal permits are required to
restrict emissions in areas that meet federal standards
for criteria pollutants |
R |
|
Radon |
a colorless,
naturally occurring, radioactive, inert gaseous element
formed by the radioactive decay of radium atoms in soil
or rocks |
Reactive Organic Gases (ROG) |
classes of organic compounds, especially
olefins, substituted aromatics and aldehydes, that react
more rapidly in the atmosphere to form photochemical smog
or ozone |
Reasonable Further Progress (RFP) |
specified rate of progress towards meeting
an air quality standard, as set forth in law or in a plan |
Reasonably Available Control Technology (RACT) |
air pollution abatement equipment that
is both technologically feasible and cost effective |
Ringelmann Chart |
actually a series of charts, numbered 0
to 5, that simulate various smoke densities, by presenting
different percentages of black. A Ringelmann No. 1 is
equivalent to 20 percent black; a Ringelmann No. 5 is
100 percent black. They are used for measuring the opacity
or equivalent obscuration of smoke arising from stacks
and other sources by matching the actual effluent with
the various numbers, or densities, indicated by the charts |
S |
|
Saturated Hydrocarbon |
an organic compound consisting of only
carbon and hydrogen atoms with no double or triple bonds.
Examples are ethane, methane and propane. They are relatively
unreactive, (i.e., do not form photochemical smog as rapidity
as other organics) |
Scrubber |
a device that uses a high energy liquid
spray to remove aerosol and gaseous pollutants from an
air stream. The gases are removed either by absorption
or chemical reaction |
Smog |
a term used to describe many air pollution
problems. Smog is a contraction of smoke and fog; in California,
it describes the irritating stagnant haze resulting from
the sun's effect on pollutants in the air |
Soot |
very fine carbon particles that appear
black when visible |
State Implementation Plan (SIP) |
EPA-approved state plans for attaining
and maintaining national ambient air quality standards |
Stationary Source |
a fixed, non-mobile producer of pollution,
usually at industrial or commercial facilities |
Storage Tank |
any stationary container, reservoir, or
tank used for the storage of liquids. District regulations
usually only apply to the storage of organic liquids |
Stratosphere |
the portion of the atmosphere that is 10
to 25 miles above the earth's surface |
Sulfur Oxides |
pungent, colorless gases formed primarily
by the combustion of sulfur-containing fossil fuels, especially
coal and oil. Considered major air pollutants, sulfur
oxides may impact human health and damage vegetation |
T |
|
Title III |
a section of the
1990 amendments to the federal Clean Air Act that deals
with the control of toxic air emissions |
Title V |
a section of the 1990 modifications to
the federal Clean Air Act that requires a federally enforceable
operating permit for major sources of air pollution |
Topography |
the configuration of a surface, especially
the earth's surface, including its relief and the position
of its natural and man-made features |
Total Organic Gases (TOG) |
gaseous organic compounds, including reactive
organic gases and relatively unreactive organic gases
such as methane |
Total Suspended Particulates (TSP) |
particles of solid or liquid matter - such
as soot, dust, aerosols, fumes and mist - up to approximately
30 microns in size |
Toxic Air Pollutants |
air pollutants that may cause or contribute
to an increase in mortality or in serious illness or which
may pose a present or potential hazard to human health |
Toxic Best Available Control Technology(TBACT) |
similar to BACT standards except applies
to sources of toxic emissions. In many cases, it is the
same as BACT. The standards are based on using the most
up-to-date methods, systems, techniques, and production
processes available to achieve the greatest feasible emission
reductions. These are the most stringent requirements
for new or modified sources and are determined on a case-by-case
basis |
Transportation Control Measures (TCMs) |
strategies to reduce vehicle trips, vehicle
use, vehicle miles traveled, vehicle idling or traffic
congestion for the purpose of reducing motor vehicle emissions |
Transportation Fund for Clean Air(TFCA) |
Air District grants to public agencies
for eligible transportation projects that reduce emissions
from motor vehicles |
Troposphere |
the layer of the
atmosphere nearest the earth's surface. The troposphere
extends outward about 5 miles at the poles and 10 miles
at the equator |
U |
|
Underground Storage Tank |
a tank located completely or partially
under ground that is designed to hold gasoline or other
petroleum products or chemical solutions |
V |
|
Variance |
permission granted for a limited time under
stated conditions for a person or company to operate outside
the limits prescribed in a regulation |
Volatile Organic Compound (VOC) |
an organic compound that evaporates readily
at atmospheric temperatures. A major precursor of ozone |
W |
|
Woodburning Pollution |
air pollution caused by emissions of
particulate matter, carbon monoxide, and odorous and
toxic substances from woodburning stoves and fireplaces |