relative biological effectiveness. A factor that is used to express the relative amount of biological change caused by a unit of energy deposited by a particular type of ionizing radiation into a specific part of the body. The RBE is complex and organ-specific. Due to its complexity, a simple parameter, called the quality factor, is applied to different types of radiation as a matter of regulatory practice for the purpose of estimating biological damage and the resulting cancer risk.

A numerical factor used to compare the biological effectiveness of different types of ionizing radiation. It is defined as the inverse of the amount of absorbed radiation of a particular type required to produce a given effect relative to the absorbed dose of a reference radiation (e.g., X rays or gamma rays) required to produce the same effect.

Relative biological effectiveness. An adjustment factor used to qualify an absorbed dose to account for its relative potential to do damage in biologic tissues. RBE is standardized to effects caused by x rays of a standard energy.

See routed bridge encapsulation.

routed bridge encapsulation. Process by which a stub-bridged segment is terminated on a point-to-point routed interface. Specifically, the router is routing on an IEEE 802.3 or Ethernet header carried over a point-to-point protocol, such as PPP, RFC 1483 ATM, or RFC 1490 Frame Relay.

Report By Exception.