Hate to admit another failure. But I think you are right. 3kg just isn't enough. I did have a second grill with another 3kg but that was having issues and I thought this one would do the trick by itself.
Also this cabin seems to have too much airflow.Didn't think it would matter that much. But guess I am wrong considering I have been in here for 2 hrs now.
Welp. Time for my backup plan then. I will buy a tent tomorrow evening and attempt again tomorrow night. Any suggestions of which types I should be looking for. I am a complete noob when it comes to it.
Also this is the charcoal am using. Not sure where I read the 90% number but i remember ordering it online after spotting it specifically
Yeah, sounds like it's best to abort this attempt. Please, for any future attempts, if after a few minutes you are not unconscious, GET OUT into fresh air.
As far as a tent, make sure it has an attached ground sheet and none of those "peak" vents. As few screened vents as possible. One entrance. You are going to have to seal any/all screens/vents. Plastic of some sort and tape, or maybe a rubberized "sealant" could work. A former member used a Regatta Malawi tent. It's one of those pop-up styles. It's only a 2-person tent, though, but should be enough room if you use small-ish metal pails to put burning charcoal into, and keep them at center of tent on bricks. Starting charcoal in chimney starters and waiting until they're burning nice and red hot before transferring to pails is how I'd do it. Then move pails into tent and wait a little more, 15 - 20 minutes, for CO to build up. Then get into tent quickly and get entrance closed.
REALLY, if after a few minutes you don't pass out, the CO level isn't high enough. Just get out to fresh air, revise your plan, and try again at another time.
The charcoal is *probably* ok, although I can't know for certain.