This term got 3 hits on 23.10.2011, and is thus unlikely to be in active use.
Medical » British Medicine
Requirements for Accreditation Scheme
RFA - RFAA - RFAAP - RFAF - RFAI - RFB - RFB&D - RFBD - RFBR - RFC
"RFAS." Abbreviations.com. STANDS4 LLC, 2016. Web. 12 Feb. 2016. <http://www.abbreviations.com/RFAS>.