It is the default, but the family is still considered.
And a link, in Dutch. I'm not sure how well you'd fare with google translate so sorry for that: http://reborntobealive.be/orgaandonatie/belgische-wetgeving-...
You can register your opt-out with a simple signed letter to the government.
I don't have the time to dig up the statistics right now, but the percentage of donors is considerably higher than, for example, in Germany, which is opt-in.
"Identify cessation of circulation (absence of circulation for a period of not less than 2 minutes and not more than 5 minutes)"
While the plain English information sheet cherry picks some severe cases..
"Generally they are patients with very severe brain injury from which they cannot recover. Less often, they are patients with terminal heart or lung failure, or have suffered a very severe spinal injury where they cannot breathe unassisted"
The actual protocol says...
"resuscitative attempts are either contraindicated on medical grounds, given that it has been determined that meaningful recovery of the patient is unlikely, or the patient (or the person with legal authority to make his or her medical decisions) has decided that resuscitative measures would be unduly burdensome."
Which pretty much gives the green light no matter what.
http://www.donatelife.gov.au/national-protocol-donation-and-...
If I got a Euro for ever time someone made that mistake... ;)