Your welcome and by the way the one here in oregon is enforcable by law. It says right on the form first page:

"Attention: This is a legal document which contains important information regarding the affected person's preferences or instructions for mental health treatment."

inside it states
"Once this form is signed and witnessed and given to the primary physician, Therapist, therapy agency and the chosen representative it is considered activated for three years. The representative MUST follow your wishes and the treating doctors must prove in court those wishes are detrimental to your health before they can go against what your representative and the Declaration for Mental Health Treatment plan states."

And the last page states the Oregon statutes numbers.

This form doesn't prevent being put into a mental health unit but your wishes must be followed just like a will must be followed or challenged in court.