PMV en PPD Calculator (ISO 7730 - Ergonomics of the Thermal Environment)
Predicted Mean Vote (PMV) is an index that predicts the mean value of the votes of a large group of persons on the thermal sensation scale, based on the heat balance of the human body.
Thermal sensation scale:

Predicted Percentage Dissatisfied (PPD) is an index that establishes a quantitative prediction of the percentage of thermally dissatisfied people who feel too cool or too warm.
PPD as function of PMV:

Source: ISO 7730 - Ergonomics of the Thermal Environment