In section 28LB of the Principal Act, for the definition of threshold level substitute —
""threshold level" means—
(a) in the case of injury (other than psychiatric injury or spinal injury), impairment of more than 5 per cent;
(b) in the case of psychiatric injury, impairment of 10 per cent or more;
(c) in the case of spinal injury, impairment of 5 per cent or more.".