Rural Free Delivery. a service of the Post Office, begun as an experiment in rural West Virginia on October 1, 1896, that provided free mail delivery to homes, primarily farmers, outside of the urban areas
Rural Fire District. An organization established to provide fire protection to a designated geographic area outside of areas under municipal fire protection. Usually has some taxing authority and officials may be appointed or elected.
An estimate (with uncertainty spanning perhaps an order of magnitude) of a daily oral exposure of a chemical to the human population (including sensitive subpopulations) that is likely to be without risk of deleterious noncancer effects during a lifetime.
This is a measure that differs from the Rfc as it is a chemical specific dose that people can be exposed to daily, by either ingestion or skin contact, without any directly attributable ill health concerns. The word 'chronic' can be used ahead of this to mean; in the long term. (See above and Chemical Specific).
RFD is a reader-written magazine focused on queer country-living and alternative lifestyles. It was founded in 1974http://www.clga.ca/Material/PeriodicalsLGBT/inven/oov/r1.htm, and has been edited at various locations and by different groups over the course of its existence. The magazine is published on a quarterly basis from Liberty, Tennessee.
rear flank downdraft. A region of dry air subsiding on the back side of, and wrapping around, a mesocyclone. It often is visible as a clear slot wrapping around the wall cloud. Scattered large precipitation particles (rain and hail) at the interface between the clear slot and wall cloud may show up on radar as a hook or pendant; thus the presence of a hook or pendant may indicate the presence of an RFD.