The “Data Layer“ field determines which indices, scales, or metadata to display on the Map Markers, graphs, and the map legend. The default field selection is “US EPA PM2.5 AQI“.
The following data layers are available to view on the PurpleAir map. Hover over a legend of the map to see messages about each of its values.
This next partition of data layers is a section of miscellaneous secondary and derivative data that describe the environment in ways other than mere particulate. Data for this section are supplied by auxiliary units within the PurpleAir sensors. Choose a data layer from the following section to present the sensor data within the standard scale.
Volatile Organic Compounds (IAQ): In select PurpleAir models, this field selection displays the Volatile Organic Compounds (VOC) in Bosch static Indoor Air Quality (IAQ) units.
Ozone (ppb): In select PurpleAir models, this field selection displays the ozone in parts per billion.
Humidity (%): This field selection displays the humidity, corrected by adding 4% as a general correction to account for heat generated by the WiFi module in a PurpleAir sensor. This will not be accurate for all situations.
Temperature (°F): This field selection displays the correction of -8°F that is applied to the temperature readings in a PurpleAir sensor. This is a general correction and may not be applicable to all situations.
Dew point (°F): This field selection displays the dew point; the temperature at which air becomes saturated with water vapor.
Humidex (°F): This field selection displays the Humidex (short for humidity index); an index number used by Canadian meteorologists to describe how hot the weather feels to the average person, by combining the effect of heat and humidity.
Temperature (°C): This field selection displays the correction of approximately -4°C that is applied to the temperature readings in a PurpleAir sensor. This is a general correction and may not be applicable to all situations.
Dew point (°C): This field selection displays the dew point; the temperature at which air becomes saturated with water vapor.
Humidex (°C): This field selection displays the Humidex (short for humidity index); an index number used by Canadian meteorologists to describe how hot the weather feels to the average person, by combining the effect of heat and humidity.
Sea Level Pressure (mbar): This field selection displays the atmospheric pressure (in millibars) converted to sea level values.
Altitude (feet): This field selection displays the sensor location altitude.
Absolute Humidity (g/m³): This field selection displays the absolute humidity; the measure of water vapor (moisture) in the air, regardless of temperature, expressed as grams of moisture per cubic meter of air (g/m³).