Informer Med
Informer Med Informer Med Informer Med

Tests for sterilisation control

- formaldehyde sterilisation

biological control

foto_33.jpg
DS-100 - a biological indicator of monitoring the steam-formaldehyde sterilization process - SPORAL Atrophaeus, SPORAL Stearothemophilus

An indicator looks like a strip of tissue-paper saturated with spore suspension of Bacillus stearothemophilus ATCC 7953 (for Forms) type and Bacillus Atrophaeus ATCC 9372 type in a single special paper wrapping protecting against contamination. Each indicator contains no less than 2.3 x 10 units capable of passing to the vegetative form (CFU).
In case of formaldehyde sterilization the test should undergo exposure in minimum 1-2% formalin within 60-90 minutes

Directions for use
  • Control indicators should be placed in at least two biggest representative packs for a particular load and put in places difficult for a sterilization agent to access.
  • An established sterilization programme in minimum 1-2% formalin should be performed within 60-90 minutes.
  • After sterilization process test indicators should be removed from the load and inoculation performed within up to 5 hours after exposure. If indicators cannot undergo incubation in a particular time they should be placed in room temperature and stay there up to 24 hours.
  • Food microorganisms control constitutes an indicator which does not undergo sterilization process.
  • Tests after use and out of date should be sterelized in an autoclave or burnt.
  • For formaldehyde sterilization a biological test for each batch is conducted.
Culture
  • Maintaining aseptic conditions a tissue-paper strip should be removed from a paper-foil bags and every strip should be placed in a separate bacteriological test-tube with TSB base (Soy Broth mode – casein – ion broth bouillon) – a bag can be cut in any place.
  • A tissue-paper strip should be fully dipped in the bouillon
  • Incubtion should last 5 days in temerature of 37 +/- 2°C.
  • In test-tubes containing tissue-paper strips there should be no growth from the indicators which underwent sterilization. When growth appears the sterilization process was not correct.
  • Test-tubes should be observed daily to state probable growth. In case of inefficient sterilization in 90% of cases the growth will appear within 48 hours. Test-tubes must be observed for 5 days.
  • In a test-tube containing an indicator which has not undergone sterilization growth should appear within 48 hours.
Standards

A product meets EN 866 standard for bilological control ISO 11138

Manufacturer

SPS Medical NY USA, Henrietta Road