Limit Values Japan - AC Level

Administrative Control (AC) Levels for chemical substances are occupational standards with legal binding. They are established and updated by a national expert meeting convened ad hoc when deemed necessary by the Japanese Ministry of Health, Labour and Welfare in response to new scientific knowledge.

As a general rule, the expert meeting organised by the Ministry discusses:

It then determines values of its own.

JSOH is a non-governmental academic society of occupational health professionals (academics and practitioners). JSOH’s Committee for Recommendation of Occupational Exposure Limits is a permanent subcommittee within the Society to which the above function has been delegated, together with that of assessing carcinogenicity and allergenicity. During preparation of OEL proposals, the Committee members give serious consideration to the TLVs proposed by ACGIH. Moreover, JSOH makes every effort to add its own perspective, particularly by taking recent and domestic publications into account.

JSOH’s new OEL proposals are published once a year in the journals “Sangyo Eiseigaku Zasshi” (in Japanese) and “Journal of Occupational Health” (in English). The full text of both journals is available on the Internet. It should be noted that once a recommendation has been made by JSOH, it is valid for one year for concerned parties to raise objections. JSOH reviews the comments, responds accordingly, and officially processes the proposal in due course. In some instances, industry raises objections as to the feasibility of the proposed OEL.

If adopted by the national expert meeting of the Ministry and thus converted into Administrative Control Levels, JSOH’s proposals imply legal obligation but are considered, in principle, to be voluntary guidance values. A fundamental lack of coherence must be acknowledged between the AC Level scheme, which is based on stationary ambient air monitoring, and JSOH recommended OELs, which refer to personal air sampling.

September 2012


Takahashi, K. and Higashi, T: The development and regulation of occupational exposure limits in Japan. Regul Toxicol Pharmacol 46 (2006), pp 120-125

Sakurai H: Brief introduction to occupational exposure limits in Japan. J Occup Health 39 (1997), pp 246-260