. " children and adults, and people with respiratory disease, such as asthma, should limit prolonged outdoor exertion (85 - 104 ppb)Unhealthy: Active children and adults, and people with respiratory disease, such as asthma, should limit prolonged outdoor exertion; everyone else, especially children, should limit prolonged outdoor exertion (105- 124 ppb)Very Unhealthy: Active children and adults, and" . . .