The Registry of Interpreters for the Deaf (RID) Standard Practice Papers (SPPs) articulate the consensus of the membership in outlining standard practices and positions on various interpreting roles and issues. While these were designed for ASL interpreters, and for several settings, there are many standards that apply to medical interpreters. To see them please go to:

http://www.rid.org/interpreting/Standard%20Practice%20Papers/index.cfm