USJC has been making ongoing efforts to reduce impacts on aquatic environments, such as contamination of effluent quality with hazardous substances, COD, nitrogen, or phosphorus, through appropriate operation management including adoption of a water-treatment system using the cutting-edge technologies. As for monitoring of effluent quality and biodiversity conservation, we continuously breed killifish in discharged water. The Killifish have bred repeatedly since FY 2012, the year following the start of monitoring. We donate the killifish for educational purposes to local elementary schools as a part of its regional contribution activities.

As other efforts to enhance safety and security in the plant, we implemented environmental analysis and confirms compliance with environmental regulations.
As part of safety risk management, we also hold safety promotion liaison conferences with partner companies annually in conjunction with an online meeting as COVID-19 infection measures. We continuously cooperate with partner companies and meets customer's expectations as a safe and secure factory.

Water quality monitoring and keeping of killifish

Efforts to Control Chemical Substances

USJC has been working to respond appropriately to regulations of each country on chemical substances contained in products and has developed a system for issuing non-use certificates of specified chemical substances in response to customer requests. We are also working to establish a Hazardous Substance Process Management (HSPM) system. We completely abolished for all products the use of chemicals containing PFOS and PFOA, which are persistent organic fluorine compound that may have an adverse effect on the ecosystem.

Compliance with Environmental Laws and Regulations

Legal Compliance

USJC maintains the management condition of legal compliance through established quarterly survey and confirmation procedures. We also work to take actions at early stages by gathering the latest information regarding amendments of laws and trends in new regulation.


  • USJC reaffirmed compliance through an internal audit based on its environmental management system and verified that there were no problems.
  • There was no occurrence of accidents or exceeding of regulatory value according to the results of environment analyses related to wastewater and exhaust gas in 2022.

Environmental Audit


USJC underwent ISO14001:2015 audit by Japan Environmental Certification Organization (JACO), and acquired ISO14001:2015 certification in March 2019.
In addition, we strive to maintain and improve our environmental management system through an environmental audit every year by internal auditors trained within our company.

Date of
United Semiconductor Japan Co., Ltd. Mie Pant
Yokohama Head Office
JACO EC18J0024 March 27, 2019 March 26, 2025