"It's sad to see workers with leaf blowers and ineffective dust masks blowing ashes and pollutants back into the air," Davis says. "This is an unhealthful practice for workers and neighbors."

In the latest set of answers to Frequently Asked Questions, the Association alerts the public that people with heart or lung problems should avoid clean-up activities and areas where dust or soot is present. For those who do clean, the Lung Association recommends:

• Wear an appropriate mask or respirator during clean up (but not for periods of more than one hour or so; give your lungs a break)
• Do not blow or sweep vigorously—this increases airborne pollutants
• Thoroughly wet dusty and sooty areas prior to clean up. Hose the ashes down into your planters and lawn. Ash actually improves soil quality for the plants. Furthermore, when ash goes into street gutters it goes downstream to pollute the urban runoff into rivers and ocean. Better to wet the ashes and then sweep up into trash cans
• Remember: ash will be in the air for several days, so outdoor clean-up efforts before the fires are extinguished may be futile. Note the County has asked all residents to conserve water
• If exposure to asbestos or other hazardous materials are suspected, do not disturb the area
• Do clean up the ash inside your home

In partnership with the County of San Diego and Community Health Improvement Partners, the American Lung Association offers online and dial-in information to the public on respiratory issues and health questions.

• Call 800-LUNG USA (800-586-4872) this week from 7 a.m. to 7 p.m. to get answers to respiratory questions
• Browse to www.lungsandiego.org for more numbers to call with medical questions, to check the Air Quality Index, and for answers to Frequently Asked Questions

The Air Quality Index Forecast is available directly from the San Diego Air Pollution Control District (APCD) at: http://www.sdapcd.co.san-diego.ca.us/air/otoday.html For a recorded Air Quality Forecast, the public can call (858) 650-4777.

The numbers below are an Air Quality Index (AQI) for Particulate Matter pollution in San Diego County. The Air Quality Index is on a scale from 0 (pristine air) to 500 (worst). An AQI of 100 usually corresponds to the maximum federal standard for that pollutant. When values are above 100, air quality is considered unhealthy.

Particulate matter, or PM, is the term for particles found in the air, including dust, dirt, soot, smoke, and liquid droplets. Some particles are large or dark enough to be seen as soot or smoke. Others are so small that individually they can only be detected with an electron microscope. PM can be suspended in the air for long periods of time, which is why air will continue to be polluted even after the skies clear from obvious fire smoke. Federal and State pollution standards focus closely on the size of particle because the smaller PM is the most dangerous to breathe. Smaller PM stay suspended in the air for a longer time, at least 7 days after big fires are extinguished.

Particulate Matter in the Body
The nose and sinuses filter out PM sized greater than about 10-20 microns. PM of 10 microns or less (measuring less than 1/100th of the thickness of a paper clip) is capable of getting past the body's natural defenses and entering the airways and air sacs. Some PM particles are trapped by the mucus that coats the major airways and then are brought out by the cilia that line them, but many of the PM particles will go deep in the lungs as far as the air sacs (alveoli). PM particles that are aerosols will eventually evaporate, but solid PM that lodges inside the alveoli will generally not emerge. Over a lifetime, the normal buildup of PM in the lungs usually doesn't impair the breathing of healthy people, but to safeguard health, air pollution standards limit the long-term exposure to PM. In the short term, however, people with sensitive lungs or heart problems can quickly experience health and breathing problems when they are exposed to high levels of PM for several days in a row.

Background facts and information

• Online graphic treatments of "How Smog Affects Your Body" at http://www.aqmd.gov/forstudents/Where_it_Hurts.htm
• The average adult breathes 25,000 times per day
• The lungs are the most exposed organ of the body. If you could spread out the total surface area of the alveoli (air sacs) in an average pair of adult lungs, it would form a microscopically-thin layer of tissue covering an area the size of half a tennis court
• Breathing through the nose (not the mouth) is a good idea because the sinuses function to cool and filter incoming air
• For more on particulate matter, browse to http://www.californialung.org/spotlight/cleanair03_particulate.html
• About 250,000 people in San Diego County suffer from asthma or its symptoms. Another 50,000 are living with emphysema, chronic bronchitis, or other kinds of lung disease