Biological indicators – Autoclaves (Steam)
Steam sterilisation (or autoclaving) is carried out by introducing saturated water vapour under pressure. In addition to the temperature effect itself, the presence of saturated water vapour is essential for killing microorganisms, their destruction being due to irreversible denaturation of cell components.
Biological indicators used to test steam sterilisation are microorganisms (spores of Geobacillus stearothermophilus, originally from ATCC 7953), prepared on filter paper as carrier material and packed in primary packaging consisting of transparent plastic film and paper which is steam-permeable.
The steam indicators fulfil the specifications in EN ISO 11138-3, i.e. an initial microbial count of at least 10⁵ CFU/unit, a D-value at 121°C of at least 1.5 min. and a Z-value of at least 6°C.
Secure your process
By using biological indicators you protect your staff and patients from bacterial infections transferred from non-sterilised utensils
We are PreSafe and ISO 13485 certified stated on your certificates for passed test to document your accreditation.
Our indicators are of high quality. We are following the guidelines from NIR to secure the highest standard of your sterilisation process.
We strive to make it as easy for you as possible. You will always have indicators in your inventory, free re-test and help to troubleshoot if needed.
How to use
Typically, autoclaving is carried out with a sterilisation time of a minimum of 15 minutes, at 121°C and pressure of 2 atmospheres, or a minimum of 3 minutes, at 134°C and 3 atmospheres. Items sterilised using steam are typically not heat-sensitive, e.g. simple surgical instruments, straight and contra-angle handpieces, reusable medical devices, surgical holloware equipment and textiles.
The efficacy of the sterilisation process is improved if the air is removed from the chamber before the introduction of steam. Achieving a vacuum may be difficult. Residual air hampers the penetration of steam into cavities in instruments, etc. The use of biological indicators is therefore recommended for both routine testing and validation/revalidation of the equipment.
For non-validated equipment and for equipment not being operated at the ‘overkill’ setting, routine testing every month is recommended, and, for validated equipment, every 3rd month or after 200-400 cycles. ‘Overkill’ means that the process has been conducted under conditions exceeding the minimum requirements for the sterilisation process in question.
The steam indicators are supplied in packs of 3 or 6. – You need 6 if you have more than one shelf in your autoclave
|75621||6 unit pack without culturing, 10⁵ CFU per unit|
|75620||3 unit pack without culturing, 10⁵ CFU per unit|
|75622||6 unit pack without culturing, 10⁶ CFU per unit (for validation)|
|98406||Culturing of 3 units|
|98407||Culturing of 6 units|
In addition, we offer a subscription scheme for monthly or quarterly testing with a 3-pack or 6-pack. All subscriptions include two deliveries every six months.
This scheme is aimed at small clinics (dentists, medical specialists, etc.) requiring regular testing.
Please find the available downloads here.
Click on the link below to download the IFU.
Simpler for the better
If you work within the field of microbiology, you might be familiar with Occam’s Razor. At SSI Diagnostica, we champion a slightly adapted version of this principle: The simplest solution is usually the best one.
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