| Dec. 1988 | Environmental Conservation Committee established |
| Apr. 1989 | Environmental Management Rules formulated |
| Apr. 1991 | Environmental Management Group established |
| Aug. 1994 | Reviewed by the Environmental Audit System in Toshiba on basis of Eco-Responsibility (EASTER); have been reviewed annually since |
| May. 1997 | ISO 14001 Certification Acquisition Project launched |
| Apr. 1998 | Environmental Conservation Manual and Enforcement Rules developed |
| Sep. 1998 | Audited and ISO 14001 Certification acquired |
| Apr. 2002 | Inclusion of the achievement of zero-emission operations to the Environmental Policies (Target year 2003) |
| Sep. 2003 | Zero-emission operations achieved (Announced in newspapers) |
| Apr. 2004 | Reduced CO2 emissions added to the Environmental Policies |