N.Y. Public Health Law § 2981
(b) The restriction in paragraph (a) of this subdivision shall not apply to:
5. Contents and form of health care proxy. (a) The health care proxy shall:
6. Alternate agent. (a) A competent adult may designate an alternate agent in the health care proxy to serve in place of the agent when:
(b) If, after an alternate agent's authority commences, the person appointed as agent becomes available, willing and competent to serve as agent: