what is the residual permissible limit in the sterilisation packaging after eo gas sterilisation.

MADHAV PAREKH

Dear,

I think the question is not how much EtO residuals still remain in the packaging (material) after sterilization and aeration. The heart of the matter is how much EtO is absorbed by the medical devices and what are the permissible limits herefor before use on a patient. (In Belgium the state of the art is 1 ppm). On the latest question Josy Holdener formulated an answer (see question Q00079).
The speed of desorption of the amount ot EtO absorbed by a medical device is depending on the kind of raw material, the construction of the device, the circumstances of desorption and the packaging material that is used.
When the EtO concentration on the product is below the maximum level, the amount in the packaging material will be no problem.

Kind regards,
Wim Renders

Dear Madhav Parekh,

"ISO 10993-7, Biological evaluation of medical devices - Part 7: Ethylene oxide sterilization residuals" gives varying allowable limits for different classes of (medical) devices. The relevant paragraphs are too long to be cited here.
You should be able to obtain a copy of this standard from your national standardization body.
In addition you might want to check national regulations on worker's and patient's safety for any further information.

Kind regards

Klaus Hahnen
Senior Technical Service Specialist
Sterilization Assurance Products
3M Laboratories (Europe), Neuss, Germany