At what angle hallpike thermal calorie test is done

Dix Hillpike manoeuvre: Patient sits on a couch. Examiner holds the patient's head, turns it 45deg to the right and then places the patient in a supine position so that his head hangs 30deg below the horizontal. Patient's eyes are observed for nystagmus. The test is repeated with head turned to left and then again in straight head-hanging position. Four parameters of nystagmus are observed: latency, duration, direction and fatiguability Ref: Dhingra 7e pg 44.