VdS offers an approval procedure for companies for the service of certified secure storage units (SSU) on the basis of the VdS 3529 guidelines.

These guidelines describe the basic requirements for service work on secure storage units and apply to service providers who carry out service work on secure storage units which are certified in accordance with European standards (e.g. EN 1143-1) and national guidelines (e.g. VdS and RAL). This includes in particular maintenance, repairs and conversions.