Is this Standard for the organization or the event?

This standard is designed for event organisers.  An event organizer is an entity that produces and/or manages all or some aspects of an event. An entity can be a company, a body or an organization. The event organizer is not necessarily the owner of the event. (definition from ISO 20121). If an event is the sole activity of an event organisation then by consequence, the standard is just for ‘the event’. However it is the event organisation that manages the event planning cycle and therefore it is still defined as the event organiser which is complying with the standard, rather than the event itself.

The standard may be used by organizations still in the process of forming sustainability protocols as well as those with existing organizational sustainable management systems in place.