Section 4674 Of Article 1. General Provisions From California Probate Code >> Division 4.7. >> Part 2. >> Chapter 1. >> Article 1.

. If the written advance health care directive is signed by witnesses, as provided in Section 4673, the following requirements shall be satisfied:
  (a) The witnesses shall be adults.
  (b) Each witness signing the advance directive shall witness either the signing of the advance directive by the patient or the patient's acknowledgment of the signature or the advance directive.
  (c) None of the following persons may act as a witness:
  (1) The patient's health care provider or an employee of the patient's health care provider.
  (2) The operator or an employee of a community care facility.
  (3) The operator or an employee of a residential care facility for the elderly.
  (4) The agent, where the advance directive is a power of attorney for health care.
  (d) Each witness shall make the following declaration in substance: