Air quality advisory issued |

Air quality advisory issued

A combination of building ozone concentrations, high temperatures and a strong inversion layer prompted an air quality advisory for sensitive individuals today and tomorrow.

“The hotter it is the more likely ozone is to form,” said Sam Longmire, air pollution control specialist for the Northern Sierra Air Quality Management District.

Prevailing wind from the Sacramento Valley will probably carry increased concentrations of ozone to Western Nevada County as the day progresses, according to an advisory from the air quality district.

Sensitive individuals include the elderly, children, asthmatics, adults with pre-existing heart and lung disease, pregnant women and people who exercise outdoors.

So far this season, ozone levels have violated fed standards for sensitive groups on three days in May and one in June, Longmire said.

Air quality is considered unhealthy for sensitive groups when it climbs above .085 parts per million or above an Air Quality Index measurement of 100. Air quality becomes unhealthy for everyone when measurements climb above 150 on the Air Quality Index.

Exposure to unhealthy ozone concentrations can result in chest pain, coughing, nausea, shortness of breath, throat irritation, headaches, congestion and chest discomfort.

“Quite a few people feel like they’re in a bad mood,” Longmire said.

Sensitive individuals are advised to avoid prolonged outdoor exertion during the late afternoon and evening when ozone levels are typically highest. Ozone levels are the lowest between 7 a.m. and noon.

Ground level ozone is created when Nitrogen oxides, called “Nox” and organic gases, emitted from vehicles, power plants and other gas-powered equipment react with sunlight.

For current ozone conditions visit

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