| 12/2004 | Certification audit – ITC, a.s. |
| 2005 | Internal audits of the Integrated management system at IES |
| 01/2006 | Supervision audit – ITC, a.s. |
| 2006 | Internal audits of the Integrated management system at IES |
| 02/2007 | Supervision audit – ITC, a.s. |
| 2007 | Internal audits of the Integrated management system at IES |
PDF documents: - ISO 9001:2000 certificate - ISO 14001:2004 certificate - ISO 18001:1999 certificate - Integrated management system policy at the IES