PSI Health Advisories

• PSI: 0 - 50 (Good)

• General Health Effects:

  Good

  Cautionary Statements:

  None for the general population

• PSI: 51 to 100 (Moderate)

• General Health Effects:

  Few or none for the general population

  Cautionary Statements:

  None required

• PSI: 101 to 200 (Unhealthy)

• General Health Effects:

  Mild aggravation of symptoms among susceptible persons ie. those with underlying conditions such as chronic heart or lung ailments; transient symptoms of irritation eg. eye irritation, sneezing or coughing in some of the healthy population.

  Cautionary Statements:

  Persons with existing heart or respiratory ailments should reduce physical exertion and outdoor activity.
  
  The general population should reduce vigorous outdoor activity.

• PSI: 201 to 300 (Very Unhealthy)

• General Health Effects:

  Moderate aggravation of symptoms and decreased tolerance in persons with heart or lung disease ; more widespread symptoms of transient irritation in the healthy population.

  Cautionary Statements:

  Elderly and persons with existing heart or lung disease should stay indoors and reduce physical exertion and outdoor activity.
  
  The general population should avoid vigorous outdoor activity.

• PSI: 301 to 400 (Hazardous)

• General Health Effects:

  Early onset of certain diseases in addition to significant aggravation of symptoms in susceptible persons; and decreased exercise tolerance in healthy persons.

  Cautionary Statements:

  Children, elderly and persons with existing diseases should stay indoors and avoid outdoor activity.
  
  The general population should avoid all unnecessary outdoor activity.

• PSI: Over 400 (Hazardous)

• General Health Effects:

  PSI levels above 400 may be life-threatening to ill and elderly persons. Healthy people may experience adverse symptoms that affect normal activity.

  Cautionary Statements:

  Children, elderly and persons with existing diseases should stay indoors, keeping the windows and doors closed and avoiding physical exertion as far as possible.
  
  Outdoor activity should be avoided.
  
  The general population should keep physical exertion and outdoor activity to as low a level as possible.

Notes: The index value refers to the 24-hour Pollutant Standards Index (PSI) value and not to the 3-hour PSI value. Only the 24-hour PSI value is correlated to the health effects outlined.