Glossary
E
A motor vehicle that uses an electric motor as the basis of its operation. Such vehicles emit virtually no air pollutants. (See also hybrid electric vehicle.)
An air pollution control device that removes particulate matter from an air stream by imparting an electrical charge to the particles for mechanical collection at an electrode. For more information, visit our associated training class on this subject.
For stationary sources, the relationship between the amount of pollution produced and the amount of raw material processed or burned. For mobile sources, the relationship between the amount of pollution produced and the number of vehicle miles traveled. By using the emission factor of a pollutant and specific data regarding quantities of materials used by a given source, it is possible to compute emissions for the source. This approach is used in preparing an emissions inventory. Visit U.S. EPA emission factors, or ARB's emission factors and toxic air contaminants.
An estimate of the amount of pollutants emitted into the atmosphere from major mobile, stationary, area-wide and natural source categories over a specific period of time such as a day or a year. For more information, visit our emissions inventory website.
A rule-making concept whereby approval of a new or modified stationary source of air pollution is conditional on the reduction of emissions from other existing stationary sources of air pollution. These reductions are required in addition to reductions required by best available control technology. For information see our New Source Review Emission Reduction Credit Offsets website.
A non-transferable or tradable allocation of entitlements by a government to an individual firm to emit a specified amount of a substance.
The weight of a pollutant emitted per unit of time (e.g., tons/year).
The maximum amount of a pollutant that is allowed to be discharged from a polluting source such as an automobile or smoke stack.
Released or discharged air contaminants in the ambient air from any source.
The amount of energy available for doing work. For example, the amount of energy in fuel available for powering a motor vehicle.
Emissions certification standard for motor vehicles; vehicle meets the requirements of an AT PZEV and has some all electric range, such as a plug-in hybrid, or has an internal combustion engine (ICE) that runs on hydrogen.
The fair treatment of people of all races and incomes with respect to development, implementation and enforcement of environmental laws, regulations and policies.
AB 32 directed ARB to convene an Environmental Justice Advisory Committee to advise ARB on the implementation of AB 32. EJAC is comprised of representatives from communities in the state with the most significant exposure to air pollution, including, but not limited to, communities with minority populations or low-income populations.
A label that provides a Global Warming Score and Smog Score, both on a scale from 1 to 10 (10 being cleanest). The Environmental Performance Label is required on all new cars sold in California that are manufactured after January 1, 2009.
Primarily a combination of sidestream smoke from the burning end of a cigarette, pipe or cigar and exhaled mainstream smoke from the smoker. Other components include smoke emitted at the mouthpiece during puff drawing. For more information, visit our environmental tobacco smoke website.
Primarily a combination of sidestream smoke from the burning end of a cigarette, pipe or cigar and exhaled mainstream smoke from the smoker. Other components include smoke emitted at the mouthpiece during puff drawing. For more information, visit our environmental tobacco smoke website.
The study of the occurrence and distribution of disease within a population.
Ethyl-alcohol, a volatile alcohol containing two carbon groups (CH3CH2OH). For fuel use, ethanol is produced by fermentation of corn or other plant products.
The chemical ethylene oxide (1,2-epoxyethane) which has been identified by the ARB and listed as a toxic air contaminant in title 17, California Code of Regulations, section 93000.
Emissions from evaporating gasoline, which can occur during vehicle refueling, vehicle operation and even when the vehicle is parked. Evaporative emissions can account for two-thirds of the hydrocarbon emissions from gasoline-fueled vehicles on hot summer days.
A measured level of an air pollutant higher than the national or state ambient air quality standards. (See also NAAQS and CAAQS.)
The legal document that indicates that a product subject to ARB regulations has in fact meet those requirements and can be offered for sale in California. The Executive Order, or EO, also lists important compliance information such as the legal description of the product and manufacturer, the actual standards met, when the executive order was granted and any conditions of the certification.
An emission control method that involves recirculating exhaust gases from an engine back into the intake and combustion chambers. This lowers combustion temperatures and reduces NOx. (See also nitrogen oxides.)
A calculated value that represents the concentration expected to occur at a particular site once per year, on average. The calculation procedure uses measured data collected at the site during a three-year period. Measured concentrations that are higher than the EPDC are excluded from the state area designation process.
The concentration of the pollutant in the air multiplied by the population exposed to that concentration over a specified time period.
Measurement or estimation of the magnitude, frequency, duration and route of exposure to a substance for the populations of interest.
F
A federal law passed in 1970 and amended in 1974, 1977 and 1990 that forms the basis for the national air pollution control effort. Basic elements of the act include national ambient air quality standards for major air pollutants, mobile and stationary control measures, air toxics standards, acid rain control measures and enforcement provisions. For more information, visit the Federal Clean Air Act.
In the absence of an approved State Implementation Plan (SIP), a plan prepared by the U.S. EPA that provides measures that nonattainment areas must take to meet the requirements of the Federal Clean Air Act.
A market-based emission fee in which the fee is levied on projected lifecycle vehicle emissions and is refunded according to an allocation formula.