## Glossary P

A **parallel** (circles of latitude) is one of a group of abstract lines on the surface of the earth formed by the latitude and longitude coordinate system: parallels represent lines of equal latitude.

A ** Particulate Matter **is a tiny (microscopic) matter in the atmosphere . It might be solid or liquid.

**Peer Review**is a documented in-depth critical examination of a proposed or actual product, generally beyond the state of the art or characterized by the existence of potential uncertainty, conducted by qualified individuals (or an organization) independent of those who performed the work but collectively equivalent in technical expertise to those who performed the original work.

*German: Pro Kopf / Español: Per cápita / Português: Per capita / Français: Per capita / Italiano: Pro capite *

**Per capita** means Per person; generally used in expressions of water use, gallons **Per capita** per day (gpcd).

**Per capita** is a Latin prepositional phrase.

The **Performance Curve** is the probability of deciding that the parameter of interest is greater than action level over the range of possible population parameters and which is used to assess the goodness of a test or to compare two competing tests; similar in concept to a statistical power curve

A **Poisson Distribution** is a probability distribution used in the statistical analysis of events which resembles the binomial distribution in that it models counts of events.

A **polychlorinated biphenyls** (PCBs) is a class of chemicals that were manufactured for industrial purposes as coolants and lubricants for electrical equipment until they were phased out in 1977. These highly persistent chemicals can still be found in older electrical equipment and in industrial waste sites.

Page 1 of 3