In this chapter, the following terms have the meanings indicated. Terms Defined. “Certified seed” or “certified oyster” means seed oysters having zero prevalence and intensity of MSX and dermo at the time of planting, as determined by current technology. “Oyster recovery areas (ORA)” means the geographic areas in the Chesapeake Bay and its tributaries designated for management actions. “Zones” means geographic areas within oyster recovery areas where specific management actions may occur and which are designated as Zones A, B, or C.