Center rescue, recovery or cleanup operations, as defined in section two of this chapter, and subsequently retired on a service retirement, an ordinary disability retirement , a performance of duty disability retirement, or was separated from service with a vested right to deferred payability of a retirement allowance and subsequent to such retirement or separation which is determined by the head of the retirement system to have a qualifying World Trade Center condition, as defined in section two of this chapter, upon such determination by the head of the retirement system it shall be presumed that such disability was incurred in the performance and discharge of duty as the natural and proximate result of an accident not caused by such member's own willful negligence, and that the member would have been physically or mentally incapacitated for the performance and discharge of duty of the position from which he or she retired had the condition been known and fully developed at the time of the member's retirement, unless the contrary is proven by competent evidence.
N.Y. Retire. and Soc. Sec. Law § 605-B