Dear sir,

can you guide me about what is the actual shelflife of ETO, PLASMA sterilized items packed in paper or tyvek pouches means for how many periods it is considered as sterilized.
please guide me about this

Thanks.
SHREEPALSINH WAGHELA

Dear,

The peremption date is not depending on the sterilization method but depends on the kind of packaging material, the manipulation(s) of the package and the conditions of storage.
Nowadays the principle of the arbitrary fixed shelflife (time related sterility) is shifting towards the principle of event related sterility. The latest requires a quality system to be in place. Questions 93, 110, 117, 176 and the EFHSS Education pages

• sterilization basics, packaging -,
• central service self study lessons
• sps education

can certainly help you further.

Kind regards,
Wim Renders

Dear,

After successful sterilization the preservation of sterility is related to preventing the ingress of micro-organisms to the sterile item. Many factors affect the extent of such ingress. From the packaging material point of view the flow rates through the layers of packaging material and the pore size plus other filtration parameters of the packaging material are the most critical. For example the following parameters of the packaging material are crucial and effect the barrier properties:

• Mechanical strenght of the materials e.g.tensile and tear strenght,elasticity, elongation, crystallization grade etc. (depend for example on the surface weight of the paper and the quantity of the layers in the laminate used - the more weight and layers the better the barrier).
• Pore size, water repellency and air permeability of the material.

All these factors should be known and considered when making the decision of the shelf life of sterilized items.

Anneli Haikonen
WIPAK MEDICAL