Horacio I do not I acess to DOE's HASL-300. Would you fax a those three pages dealing with MDA to me as well. Thanks, Phillip FAX # 205.386.2370
There is a very simple derivation of this in the Procedures Manual of the US DOE's Environmental Measurements Laboratory (HASL-300). I'd be glad to fax you the relevant pages; they include a brief bibliography. I don't think that you really need the +3, unless you have a very small number of counts. A more lengthy treatment is in the draft ANSI standard on bioassay, which I believe was withdrawn. Chris Alston