Who's cleaning up the air?
The Air Resources Board (ARB) is California's air pollution control agency. Our job is to clean up the state's air. The ARB provides funding for research projects, sets air quality standards, monitors levels of various air pollutants, and sets and enforces regulations to reduce air pollution. The ARB focuses on reducing air pollution emissions from cars and trucks, fuels, and consumer products; and emissions of toxic air contaminants. The ARB also works with the local air pollution control districts (APCDs) to reduce air pollution from stationary sources such as factories and power plants.
Air pollution research
Fifty years ago, scientists didn't know much about the causes and effects of air pollution. Since then, research has revealed a lot about the effects of dirty air on people, the environment, and the economy. Today, the ARB and other air quality agencies sponsor scientific research projects that helps us understand where air pollution comes from, how it affects our health, and how to reduce or eliminate sources of air pollution.
Air pollution research helps guide the ARB in setting air quality standards and developing new ways to clean up the air.
Air quality standards
How much air pollution is too much? The ARB has developed ambient (that means outdoor) air quality standards for the most harmful air pollutants in California. These include ozone, particulate matter (called PM10), carbon monoxide, nitrogen dioxide, lead, sulfur dioxide, visibility reducing particles, sulfates, and hydrogen sulfide.
Air quality standards are legal limits that identify the maximum pollution levels considered acceptable. Research shows that higher levels can threaten the health of the general public. The ARB and United States Environmental Protection Agency set state and federal air quality standards, respectively.
An air quality standard includes the maximum concentration level and time an air pollutant can be present in the air before it begins to cause health problems. For example, the California air quality standard for ozone is 9 parts per hundred million for one hour. That doesn't seem like much, but researchers have discovered that breathing that much ozone for an hour can hurt your health.
The problem pollutants
Ozone and particulate matter are the pollutants that still reach unhealthy levels in many areas of the state. Carbon monoxide is a problem in a few local areas.
What about chemicals that are referred to as toxics or toxic air contaminants?
Toxic air contaminants
Toxic air comtaminants (TACs) are air pollutants, identified in regulations by the ARB, which may cause or contribute to an increase in deaths or in serious illness, or which may pose a present or potential hazard to human health. Examples of TACs are benzene (found in gasoline) and diesel exhaust particulates. TACs are regulated differently than the major pollutants listed above because their health effects may occur at extremely low levels. Setting standards doesn't make sense because often these pollutants are unsafe at any level. Instead, the ARB and APCDs establish control measures to reduce the risk to people who might be exposed to specific TACs.
Air quality monitoring
How do we know if air pollution has reached unhealthy levels? Monitoring stations around the state regularly measure air pollutant levels.
This is a monitoring station in Sacramento that tracks both pollution and weather conditions. The ARB and local APCDs operate monitoring stations like this in many areas of California. The stations measure the levels of major pollutants such as ozone, carbon monoxide, and particulate matter. Some stations also measure the levels of toxic air contaminants.
Air Quality Index (AQI)
The Air Quality Index or AQI was developed by the U.S. EPA to provide accurate, timely and easily understandable information about daily levels of
ozone and particulate matter air pollution. Newspapers, TV, radio, and web sites usually report pollution levels in terms of the AQI.
When we understand how much our activities, climate, and terrain affects air pollution levels, then air quality scientists can predict when air pollution will reach unhealthy levels. This information shows us when and where we need to reduce polluting activities such as driving, agricultural burning, or using our fireplaces. Some areas in California have "Spare the Air" programs. If a dirty air day is predicted, the news media alert the public to reduce polluting activities.
If our air is polluted, what is being done to clean it up?
Reducing air pollution
The ARB and APCDs pass regulations to reduce or control air pollution. California's air pollution problem is so serious that almost every kind of equipment, product, or business is subject to air pollution regulation.
Regulations that help to reduce air pollution include those requiring the use of gasoline that burns cleaner and evaporates less, consumer products that contain fewer smog-forming chemicals, and requirements for very low-emission and zero-emission vehicles such as electric cars. Other regulations that help to control air pollution include those requiring smog controls like catalytic converters on cars and electrostatic precipitators and baghouses on factory smokestacks.
A regulation sets limits on the release of certain air pollutants into the air from a particular source. These levels are called emission standards. For example, California's emission standards for passenger cars limit the amounts of reactive organic gases, nitrogen oxides, and carbon monoxide that a car can emit per mile. The ARB and APCDs set emission standards limiting the amount of air pollution from stationary sources such as factories; mobile sources such as cars and trucks; fuels such as gasoline and diesel; and consumer products such as hairsprays and automotive cleaning products.
Are these regulations working?
ARB enforces regulations
To make sure that businesses comply with air pollution regulations, ARB and APCD inspectors conduct periodic checks of air pollution sources. They take fuel samples at refineries and service stations, test emissions from cars and trucks, and get lab analyses on the amount of smog-forming ingredients in consumer products. If the tests or lab analyses show there is a violation, then the inspector issues a notice of violation and the company must fix the problem and may have to pay a fine.
But the best test of how well air pollution regulations are working is to check the air. Is the air getting cleaner?
Is the air cleaner?
When we compare air pollution levels through the years, we can see if the air is getting clearer or dirtier. The graph shows how the level of one air pollutant, ozone, has changed in California since 1980.
This graph shows that the ozone levels in California are about half of what they were in 1980. That's good. However, today's levels of ozone are still unhealthy. Therefore, the ARB and APCDs continue to do more to clean the air. We will make sure that cars, trucks, and other products pollute even less in the future. But we need everyone's help, including yours!
For more details about air pollution trends in your area, check out the air quality pages at ARB's web site.
For more suggestions, check out Whatcha Doin' About Air Pollution and