An ERD (Entity Relationship Diagram) is a graphical representation of the data in rest within a system (e.g. a business, an organization, an application) that is subject to analysis.
The U.S. EPA established the Reference Dose (RfD) Work Group to address these concerns. In preparing this report, the RfD Work Group has drawn on traditional report on risk assessment (NRC, 1983), to more fully articulate the use of noncancer, nonmutagenic experimental data in reaching regulatory decisions about the significance of exposures to chemicals.
In the process, the Work Group has coined less value-laden terminology -- reference dose (RfD), uncertainty factor (UF); margin of exposure (MOE); and regulatory dose (RgD) -- to clarify and distinguish between aspects of risk assessment and risk management.