Air Quality Advisory for Mon., July 7, through Thurs., July 10, 2008

Advisory for Monday July 7 through Thursday, July 10, 2008

Placer County, CA July 7, 2008 – Widespread smoky conditions continue to affect Placer County from the valley floor to the Lake Tahoe area from fires inside and outside of the county. Average concentrations of fine particulates (PM2.5) continue to fluctuate throughout the day, with conditions ranging from hazardous to moderate.

With the continued smoke episode, Tom Christofk, Placer County Air Pollution Control Officer and Dr. Richard Burton, MD, Placer County’s Health Officer, are issuing this updated air quality advisory for July 7^th through July 10^th. The weather forecast for this week with the strong high pressure, very warm temperatures and little wind, combined with smoke, make for very stagnant conditions.

With cooler temperatures in the early morning, smoke tends to move down the western slope becoming more concentrated in foothill locations. In the afternoon hours and early evening, conditions appear to improve in the foothills as smoke rises into higher elevations, including the Lake Tahoe area.

The public is reminded to take common-sense precautions as Placer County will continue to be affected by very unhealthy or even hazardous air quality at times. If visibility is poor in your area, then you should strongly consider postponing outdoor activities until later in the day or when conditions improve.

Particulate matter, found within smoke from fire, contains a multitude of particles, such as wood tar vapors and toxic gases. Other pollutants found in smoke are carbon monoxide, nitrogen oxides, and hydrocarbons. Scientific studies have linked the fine particles associated with smoke with a variety of significant health problems. Symptoms include eye irritation, throat irritation, and coughing. People with existing heart and lung disease, including asthma, may experience heightened symptoms. They should monitor their health and consult with their health care provider should their symptoms worsen. Even healthy people may experience some of these symptoms in smoky conditions. Seek medical help if you experience symptoms that worsen or become severe.

Dr. Burton and Christofk urge residents to keep in mind the following recommendations when they are in smoky conditions:

• Healthy people should delay outdoor strenuous exercise.

• Children and elderly people should avoid outdoor activities, particularly prolonged outdoor exertion.
• People with specific illnesses, particularly respiratory problems, should remain indoors.
• Using paper mask filters, which are not capable of filtering extra-fine smoke particles, and which restrict airflow, is not recommended.
• Stay inside with doors and windows shut. Use the recycle or recirculate mode on the air conditioner in your home or car. Avoid cooking and vacuuming, which can increase pollutants indoors.
• Asthmatics should follow their asthma-management plans.
• Contact your doctor if you have symptoms such as chest pain, chest tightness, shortness of breath, or severe fatigue. This is important for not only people with chronic lung or heart disease, but also for individuals who have not been previously diagnosed with such illnesses. Smoke can “unmask” or produce symptom of such diseases.
• Keep airways moist by drinking lots of water. Room humidifiers might also provide some comfort.

Use the following index to assess the air quality based on the visibility in a given area:

• Face away from the sun. Determine visibility range by looking for targets that are at known distances (miles).
• The visible range is the point where even high-contrast objects disappear.
• After determining visibility in miles use the following Wildfire Smoke Visibility Index to assess air quality.

Visibility Range	Health Category	Cautionary Statements
10+ miles	Good	None
5 – 10 miles	Moderate	Usually sensitive people should consider reducing prolonged or heavy exertion.
3 – 5 miles	Unhealthy for Sensitive Groups	Sensitive people should reduce prolonged or heavy exertion.
1.5 – 2.5 miles	Unhealthy	Sensitive people should avoid prolonged or heavy exertion. Everyone else should reduce prolonged or heavy exertion.
1 – 1.25 miles	Very Unhealthy	Very Unhealthy Sensitive people should avoid all physical activity outdoors Everyone else should avoid prolonged or heavy exertion.
<0.75 miles	Hazardous	Sensitive people should remain indoors and keep activity levels low. Everyone else should avoid all physical activity outdoors.

Information will be updated and posted to the District Web site as available at www.placer.ca.gov. For general air quality information go to www.sparetheair.com. The Spare the Air website is a great site to monitor current air quality values for ozone and PM2.5. Smoke formation generates an increase in PM2.5 concentrations and the higher the concentration, the higher the Air Quality Index value. Before conducting any outdoor activities it would be prudent to visit this sight to review the Index and forecast for your area. If information is not provided for your general area, use the visibility index provided above to determine air quality.

Following is the Air Quality Index table for Particle Pollution for reference.

Air Quality Index (AQI)