Boston, MA

Any exposure to the air, even for a few minutes, can lead to serious health effects for anyone. Avoid outdoor activities

Health effects will be immediately felt by sensitive groups and should avoid outdoor activity. Healthy individuals are likely to experience difficulty breathing and throat irritation; consider staying indoors and rescheduling outdoor activities

Health effects can be immediately felt by sensitive groups. Healthy individuals are likely to experience difficulty breathing and throat irritation with prolonged exposure. Limit outdoor activity

The air quality has reached a high level of pollution and is unhealthy for sensitive groups. Reduce time spent outside if you are feeling symptoms such as difficulty breathing or throat irritation

The air quality is generally acceptable for most individuals. However, sensitive groups may experience minor to moderate symptoms from long-term exposure

The air quality is unaffected for most individuals. Enjoy your normal outdoor activities

The air quality is unaffected for most individuals. Enjoy your normal outdoor activities