The methods of killing must be appropriate to the species, in all cases producing
immediate unconsciousness without pain or panic and inevitable subsidence to death without the regaining of consciousness.
Exclusion criteria were
unconsciousness for more than 15 minutes after the accident or having no memory of the accident, history of psychosis, current alcohol or other substance dependence, borderline personality disorder, severe depression needing
immediate treatment in its own right (suicide risk), and treatment or assessments that could not be conducted without the aid of an interpreter.