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API and You

Air Pollution Index and Air Quality

What does the API tell us? The API ranges from 0 to 500 and is divided into 5 bands according to the potential effects on health. An API number of 100 is particularly important since it corresponds to the short-term Air Quality Objective values (i.e. 1-hour and 24-hour limits). An API higher than 100 means that one or more pollutants may pose immediate health effects to some susceptible members of our community. It should be noted that for an API in the range of 51 to 100, although immediate health effects are not expected for the general population, long-term effects are possible if this level of air pollution persists. The potential health effects for different ranges of API values are as follows: Air Quality Status Air Pollution Level API   Health Implications [1] Air quality significantly worse than both short-term and long-term AQOs. Severe 201 to 500 People with existing heart or respiratory illnesses may experience significant aggravation of their symptoms and there will be also widespread symptoms in the healthy population. These include eye irritation, wheezing, coughing, phlegm and sore throat. Air quality worse than both short-term and long-term AQOs. Very High 101 to 200 People with existing heart or respiratory illnesses may notice mild aggravation of their health conditions. Generally healthy individuals may also notice some discomfort. Air quality within the short-term AQOs but worse than the long-term AQOs. High 51 to 100 Very few people, if any, may notice immediate health effects. Long-term effects may, however, be observed if you are exposed to such levels for a long time. Air quality within all AQOs. Medium 26 to 50 None to the general population. Air quality well within all AQOs. Low 0 to 25 None to the general population. [1] The health implications set out above serve as a broad guide only as a gradual increasing risk of effects is expected as pollutant concentrations rise.

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