convert_to_index: Convert a pollutant concentration to its air quality category
Description
This functions converts a pollutant value in its original units into one of the 5
categories used by the Mexican government to communicate to the public how
polluted the air currently is and its health risks.
Usage
convert_to_index(value, pollutant)
Value
the IMECA value of the concentration indexed into 5 categories
BUENA - Good: 0-50 minimal health risk
REGULAR - Regular: 51-100 moderate health effects
MALA - Bad: 101-150 sensitive groups may suffer adverse heatlh effects
MUY MALA - Very Bad: 151-200 everyone can experience negative health effects
EXTREMADAMENTE MALA - Extremely Bad: > 200 serious health issues
Arguments
value
a numeric vector of values to convert to index
pollutant
type of pollutant. A vector of one or more of the following
options:
SO2 - Sulfur Dioxide - ppb (24 hour average)
CO - Carbon Monoxide - ppm (8 hour average)
NO2 - Nitrogen
Dioxide - pbb (1 hour average)
O3 - Ozone ppb (1 hour average)
PM10 - Particulate matter 10 micrometers or less (24 hour
average)
PM25 - Particulate matter 2.5 micrometers or less (24
hour average)