Autoclave Test: BTSure Biological Indicator SOP

Categorized: Peptides


  1. Remove an appropriate number of BTSure units from the box.
    • Remove one unit for each area of the autoclave to be tested and one additional unit to be used as a positive control (this one will not be placed in the autoclave).
  2. Label indicators with appropriate process information.
  3. Place each unit into a small beaker in a horizontal position with representation materials to be sterilized.
    • Cover the beakers with aluminum foil.
  4. Place beakers inside the autoclave.
    • One of the beakers should be situated so that it is directly over or next to the drain. The area surrounding the drain is the coolest part of the autoclave and considered to be the least effective area for sterilization.
    • The positive control should not be placed in the autoclave
  5. Operate the autoclave per autoclave SOP.
  6. Operator shall put the thermal insulated gloves on prior to removing materials from autoclave.
  7. Remove the beakers from the autoclave; allow indicators to cool for at least 10 minutes.
  8. Remove BTSure biological indicators from the beakers.
    • Observe colour change (blue to black) of the chemical indicator on the BTSure label. NOTE: Colour change indicates exposure to steam. It does not indicate acceptable sterilization.
  9. Incubation

    • Place an indicator into the crusher in an upright position and squeeze the crusher to break the glass ampoule. This will allow the strip to be immersed in the media.
    • Repeat the crushing with each additional indicator including the positive control.
    • Immediately place the indicators (including the positive control) into the incubator.
    • Incubate at 55 to 60°C for at least 48 hours.
    • Examine indicators at regular intervals for any change in colour and record results.
      • The positive control tube should change from purple media to yellow. If it does not, the study is invalid and needs to be repeated with a new lot of indicators.
      • The sample indicators should not change colour. No colour change (media remains purple) indicates adequate sterilization.
      • If the sample indicators turn yellow this indicates bacterial growth and an investigation will need to be conducted. This may include re-performing the autoclave cycle.
    • Report any indication of bacterial growth to instructor or lab manager.
    • Dispose of all used BTSure tubes in a biohazard sharps receptacle when finished.