From the Alberta Mental Health Act.....
II. Who Does the Act Apply To?
To be admitted and detained in a hospital involuntarily, you must meet all three of the following conditions, which are explained in more detail below:
1. Mental Disorder
You must have a mental disorder or you must be apparently suffering from a mental disorder.
2. A Danger to Self or Others
You must be in a condition that presents a danger to yourself or to others, or are likely to do so.
3. No Alternative
You must be unsuitable for admission in any other way. This is generally understood to mean that you refuse to be admitted voluntarily.
IV. How Long Can I Be Kept?
The first admission certificate expires within 24 hours from the time of arrival at the hospital, unless a second admission certificate is completed within that time. Two admission certificates allow the hospital to keep you for up to one month from the date of the second certificate.