The Northern Sierra Air Quality Management District is updating and
expanding its air quality health advisory for July 27 and 28.  Smoky
conditions are likely to be experienced in parts of Plumas, Sierra and
Nevada County due to smoke from the Lowell Fire in the Steephollow Creek
area of Nevada County.

During the night and early morning of July 26 and 27, air quality reached
the Very Unhealthy to Hazardous range in western Nevada County as
downslope, nighttime winds pushed smoke into Grass Valley, Nevada City and
surrounding areas.  The main smoke plume is expected to shift to the
northeast during Monday, and could result in smoky conditions primarily in
the eastern portions of Sierra and Plumas County, and possibly reach
Truckee in Nevada County.  Some of the overnight smoke drifted down the
Bear River drainage toward the Central Valley floor and is expected to
gradually drift northeast across Nevada County during Monday, with gradual
clearing likely in western Nevada County as the day progresses.  It is
possible that the morning of July 28 will be smoky in western Nevada County
again.

Smoke is primarily fine particulate matter less than 2.5 microns in
diameter (PM 2.5), which can be inhaled deeply into the lungs.  Smoke
concentrations are expected to intermittently be in the Unhealthy for
Sensitive Groups range and potentially reach the Hazardous range over a
wide area on Monday and Tuesday, and are expected to vary greatly during
the course of each day depending on wind speed, wind direction, fire
behavior and other factors.

Aggravation of heart or lung disease, sever breathing difficulty and
premature mortality could occur in people with cardiopulmonary disease and
older adults, while increased respiratory effects may be evident in the
general population.  People with heart or lung disease, older adults and
children are especially sensitive to the health effects of smoke and should
avoid physical activity outdoors.  Everyone else should reduce prolonged or
heavy exertion.

If you smell smoke, or see smoke around you, consider restricting your
outside activities.  Until the potential for poor air quality subsides,
individuals should consider taking the following actions:
– Healthy people should delay strenuous exercise when they can smell and
see smoke. That applies especially to school gym classes and athletic
practices. Young athletes are considered sensitive  individuals and any
perceived benefits from a smoky workout could be outweighed by the negative
impacts of the smoke inhaled during that workout.
– People with respiratory illnesses should remain indoors when smoke can be
seen or smelled outside.
– Asthmatics should follow their asthma management plan.
– 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 symptoms of such diseases.
– If possible, sensitive individuals should consider relocating to another
location that is not currently experiencing smoke impacts for a few days to
avoid long term exposure.
– Keep airways moist by drinking lots of water. Breathing through a warm,
wet washcloth can also help relieve dryness.

In general, when smoke concentrations are elevated it is advisable to stay
indoors with windows and doors closed and set air-conditioners on
“re-circulate.”  Do not run swamp coolers or whole house fans. When
feasible, pets should be brought indoors when outdoor air quality is poor.
Warning: particulate respirators will not provide complete protection in
very smoky conditions and may even interfere with proper breathing. It
should also be noted that there is some controversy surrounding the use of
particulate respirators because of the many variables that may hinder their
proper use.  Masks can create a false sense of security and should not
replace reducing activity or exposure.  If you need to wear a mask, wear
the correct type of mask – disposable particulate respirators found at
hardware stores can be effective at reducing exposure to smoke particles as
long as they seal closely to the wearer’s face. Look for respirators that
have two straps and have the words “NIOSH” and either “P100” or “N95”
printed on the filter material.

Studies have linked fine particulate matter (smoke) with work and school
absences, respiratory related hospital admissions and health problems,
including burning eyes, aggravated asthma, acute respiratory symptoms
(including severe chest pain, gasping, and aggravated coughing), chronic
bronchitis, decreased lung function, and premature death.  Increased ozone
exacerbates these health effects.  In addition to the acute health effects
of smoke, people may experience some cumulative effects, such as a dry
cough and chest discomfort.

—