 
    Certification
| OHSAS 18001 - REPLACED BY ISO 45001:2018 | |
|---|---|
| July 2003 | Obtained DNV - OHSAS 18001:2004 certification | 
| July 2008 | Obtained DNV - OHSAS 18001:2007 certification ( revised version ) | 
| July 2009 | Qualified for DNV - OHSAS 18001:2007 annual auditing | 
| April 2020 ~ present | Obtained DNV - ISO 45001:2018 certification | 
|  | On the effectiveness of institutions and employees: 
 | 
| ISO 14001 | |
|---|---|
| April, 2008 | Obtained DNV - ISO 14001:2004 certification | 
| April, 2009 ~ April, 2015 | Qualified for DNV - ISO 14001:2004 annual auditing | 
| April, 2016 | Obtained DNV - ISO 14001:2015 certification ( revised version ) | 
| April, 2017 ~ present | Qualified for DNV - ISO 14001:2015 annual auditing | 
|  | On the effectiveness of institutions and the environment: 
 | 
