The air is fresh and you can go out for activities.
Fine particles: tiny particles that penetrate deep into the respiratory tract; a major cause of haze; high levels can affect respiratory health.
Nitrogen dioxide: mainly from vehicle exhaust and industrial emissions; pungent odor; irritates the nose, mouth, and lung mucosa.
Ozone: formed by photochemical reactions on sunny afternoons; often exceeds limits in summer; irritates eyes, nose, and throat; take precautions outdoors.
Inhalable particles: often from dust, sandstorms, and construction dust; may cause throat discomfort and respiratory sensitivity.
Carbon monoxide: colorless, odorless toxic gas from incomplete fuel combustion; excess inhalation can cause hypoxia.
Sulfur dioxide: mainly from coal-burning industrial emissions; irritating; affects the respiratory tract and contributes to acid rain.