MagnaAmp is a self-contained ampoule biological indicator ampoule for monitoring steam sterilization of liquids in ampoules, large containers, or washer sterilizers. The MagnaAmp biological indicator ampoules contains Geobacillus stearothermophilus spores and a specially-formulated culture medium that turns a dramatic yellow if spores grow. The MagnaAmp provides easy visual confirmation of sterilization within 48 hours, without the need for difficult and time-consuming laboratory work.