Masks that have undergone sterilization methods such as ethylene oxide (EO) are called sterilization-grade masks (the outer packaging needs to be marked with sterilization grade). Unsterilized products will be marked on the outer packaging as non-sterile grade, common grade, etc.
In medical places that strictly control the microbial environment (such as ICU, operating room, etc.), all the items entering it need to meet the sterility standard, so it is required to wear sterilization-grade medical masks. In places with sterility requirements, sterilization-grade masks are usually used. But in ordinary occasions, both ordinary grade and sterilization grade can be used.
The sterilization method of mask products is usually ethylene oxide (EO). The penetrating force is very strong, which can achieve the effect of effective sterilization without damaging the items. The principle is to cause the death of microorganisms through a series of chemical reactions [2], so as to achieve the sterilization effect.
my country’s medical device products have relevant national standards. When the relevant values of ethylene oxide residues meet the national standards, they can be used normally. (The sterilization grade medical mask requires the ethylene oxide residue to be less than 10μg/g as a safety standard, and the sterilization grade national standard children’s hygiene mask requires the ethylene oxide residue to be less than 2μg/g)
There is also a national standard for the maximum allowable residual amount of EO on a unit product after sterilization of medical devices with ethylene oxide (EO), GB/T 16886.7-2015 “Biological Evaluation of Medical Devices Part 7: Ethylene oxide sterilization” Bacterial Residues”. Among them, the allowable limit of short-term contact devices (devices with single, multiple repeated use or contact within 24h) is 4mg (average daily amount); the EO tolerable exposure limit of surface contact devices should not exceed 10μg/cm², or Should show very slight irritation responses within the limits specified in ISO 10993-10.
