(a)  Whenever a donor of a power of attorney designates another his or her attorney in fact or agent by a power of attorney in writing and the writing contains the words “This power of attorney shall not be affected by the incompetency of the donor”, or “This power of attorney shall become effective upon the incompetency of the donor”, or similar words showing the intent of the donor that the authority conferred is exercisable notwithstanding the donor’s incompetency, the authority of the attorney in fact or agent is exercisable as provided in the power on behalf of the donor notwithstanding later incompetency of the donor at law or later uncertainty as to whether the donor is dead or alive, and unless it states a time of termination, the authority conferred remains exercisable notwithstanding the lapse of time since the execution of the instrument. All acts done by the attorney in fact or agent pursuant to the power during any period of incompetence or uncertainty as to whether the donor is dead or alive have the same effect and inure to the benefit of and bind the donor or the donor’s heirs, devisees, and personal representative as if the donor were alive and competent. If a guardian or conservator subsequently is appointed for the donor, the attorney in fact or agent, during the continuance of the appointment, accounts to the guardian or conservator rather than the donor. The guardian or conservator has the same power the donor would have had if the donor were not incompetent to revoke, suspend, or terminate all or any part of the power of attorney or agency.

(b)  Any person who acts in good faith reliance on a power of attorney, whether such power is authorized pursuant to subsection (a) of this section or is otherwise valid on its face, shall incur no liability as a result of acting in accordance with the instructions of the attorney in fact or agent.