Criteria A・Criteria Bの判定基準は下記の通りです。
<Criteria A>
・細菌→7日後：接種菌数に比べ3 log以上の減少。
14日後：接種菌数に比べ3 log以上の減少、かつ7日後に比べ増加がないこと。
28日後：接種菌数に比べ3 log以上の減少、かつ14日後に比べ増加がないこと。
・酵母→7日後：接種菌数に比べ1 log以上の減少。
14日後：接種菌数に比べ1 log以上の減少、かつ7日後に比べ増加がないこと。
28日後：接種菌数に比べ1 log以上の減少、かつ14日後に比べ増加がないこと。
・カビ→14日後：接種菌数から増加がないこと。
28日後：接種菌数に比べ1 log以上の減少、かつ14日後に比べ増加がないこと。
<Criteria B>
・細菌→14日後：接種菌数に比べ3 log以上の減少。
28日後：接種菌数に比べ3 log以上の減少、かつ14日後に比べ増加がないこと。
・酵母→14日後：接種菌数に比べ1 log以上の減少。
28日後：接種菌数に比べ1 log以上の減少、かつ14日後に比べ増加がないこと。
・カビ→14日後：接種菌数から増加がないこと。
28日後：接種菌数から増加がなく、かつ14日後に比べ増加がないこと。
各Criteriaの説明（ISO 11930より抜粋）は下記の通りです。
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The criteria representing the protection capacities of a cosmetic formulation are:
— criterion A, whereby the formulation is protected against microbial proliferation that may present
a potential risk for the user and no additional factors are considered [see 6.2 a)];
— criterion B, whereby the level of protection is acceptable if the risk analysis demonstrates the
existence of control factors not related to the formulation indicating that the microbiological risk is
tolerable for the cosmetic product [see 6.2 b)].
6.2 Case 1 — Preservation efficacy test has been performed on the formulation
a) If the formulation meets criterion A, the microbiological risk is considered to be tolerable (the
cosmetic product is protected against microbial proliferation that may present a potential risk for
the user) and the cosmetic product is deemed to meet the requirements of this document without
additional rationale.
b) If the formulation meets criterion B, the microbiological risk analysis shall demonstrate the
existence of control factors not related to the formulation; for example, a protective package such
as a pump provides a higher level of protection than a jar (see Annex D). This would be considered a protective device for risk reduction.
Hence, if the risk analysis demonstrates the existence of control factors, the cosmetic product
is deemed to meet the requirements of this document on the basis of criterion B plus additional characteristics indicating that the microbiological risk is tolerable.
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