The Emergency Change process flow skips the Assess state and advances directly to Authorize state for approval. 

Approvals are unique based on the affected CIs and service.

A emergency change is used when a change must be introduced as soon as possible.

The emergency change procedure is reserved for changes intended to repair an error in an IT service that is negatively impacting the business to a high degree.  Emergency changes stress the IT change management system and should not be used to compensate for poor planning.   Emergency changes must be for exceptions and not become a shortcut to getting changes into production for any reason.

An emergency change is sometimes required and while time is of the essence, it should be designed carefully and tested as much as possible before implementation.  The impact of the emergency change may be greater than the original incident that instigated the change. 

A post implementation review (PIR) must be performed.