Advance Health Care Directives usually require a physician to certify that the granting patient is unable to give directions concerning medical care. Each medical facility has its own version of this form, which may be called an Advance Directive to Physicians or some other similar name. I advise my clients to utilize the form their usual hospital uses. For instance, if they are enrolled in Kaiser, I advise them to use the Kaiser form. Depending upon their wishes concerning the degree of medical treatment a client wishes to receive, I also advise them to discuss, obtain and sign the treating hospital's DNR (Do Not Resuscitate) Order if that is consistent with their wishes. The DNR Order makes the Advance Directive more efficient for clients who do not want their medical providers to take "heroic" measures to preserve their lives.
Springing durable powers of attorney generally refer to durable powers of attorney for asset management and decision making. A "Springing" power requires one or two physicians to certify the grantor of the power is incapacitated to the extent he or she cannot manage his or her affairs. The alternative is an immediately effective durable power of attorney which becomes effective upon delivery to the nominated Agent/Attorney-in-fact. This power of attorney is called a "durable" power of attorney because, unlike a plain power of attorney, it remains effective if the grantor becomes incapacitated. Durable powers of attorney terminate on the death of the grantor. This can be a complex area. Consultation with a knowledgeable estate planning attorney is very helpful.
East state has statutes that govern these documents. The documents themselves should set the conditions. Attorneys can have several forms that can be used - depending on state law and the objectives of the persons who is giving the powers. Whe you speak of "neutral person" this will probably mean a physician, not just any neutral person. If a Durable Power of Attorney is not a springing power, it becomes effective when it is signed. Generally, a health care power is effective if the principal (person who gives the power) is capable of making his or her own decisions concerning health care. Look at the individual documents, to see what conditions must be met before the documents become effective for the agent to act.
Ms. McMahon is correct - the forms used for these documents vary based on state law.
Since you are in California I am including a link below to the "model" form from the Probate Code, but no specific form is required. The agent's authority under this form requires an assessment by the patient's "primary physician", unless the patient indicates otherwise on the form.
Other states - most have model forms and easily "Googleable" websites with similar information.
This response is intended to provide general information, but not legal advice. The response may be different if there are other or different facts than those included in the original question. See MKnutsonLaw.com for more information on why this communication is not privileged or create an attorney-client relationship.
California has statutory suthorization for the "Advance Health Care Directive" California Probate Code Section 4701.
I generally prefer to use the form published by the California Medical Association, which comes with clear instructions. Call them at 800 882 1262.
These forms are usually recognized by physicians and may avoid having to have the form reviewed by the hospital legal department when needed.