Trying to do this in a room is tough compared to doing this in a much smaller space like a car- there is so much more oxygen to displace. Maybe in a small bathroom it woudl work better, but you have to make sure it is airtight and you want to make sure smoke alarms are off just in case. IN something like a bedroom I hvae seen failed attempts here, not sure how tough it is in a room this size.
Just about any "space" you do it in is going to leak. A tent is good. That's what I'll be using. You can only seal something so much. I'll be doing a limited amount of sealing. After that, the best way to be successful is to make sure you are generating CO at a faster rate than you are losing it. Remember CO is a gas. A tent, ANY tent, when subjected to rain over a period of time, WILL start leaking water through the fabric once it becomes saturated enough. And water molecules are larger than gas molecules. So, smaller CO gas molecules will be leaking continuously through the fabric. I'll starting my testing with 3 buckets of charcoal, with an amount in each that is counted out by lump (briquette), and not weighed. That will make it easier for anyone else, so there will be no need to purchase a scale to weigh charcoal. I'll measure and record how long it takes to get to needed CO levels and how long it is sustained. I'll repeat successful testing at least 3 times to make sure it can be duplicated successfully. To start, I only plan on sealing the seams using some cheap Dollar Tree caulking and a paint brush, and taping some inexpensive garbage bags over the couple window vents. Right now with the tent, the charcoal, the buckets, and the chimney starters, I have roughly about $190 in materials. The CO meter will be another $375 thereabouts. A couple tubes of caulk will only be another few bucks, and I have garbage bags around the house. I bought a good tent, but I suspect just about any tent would work. The important thing is to make sure it has an attached floor and only one entrance and as few vents as possible. Even cheaper $30 tents could work, but might require more sealing.
And as you said, a car can work, too. Many people have been successful in cars. I chose a tent because I am very confident that I can get CO levels very high, well above 10000 PPM, which is what you really want. That way, unconsciousness comes on within seconds and death follows quickly afterward. There's a chart floating around that shows at CO levels of 10000 PPM, unconsciousness sets in around 15 seconds or so, even faster at levels around 12000 PPM. That's WAY faster than N. Once you're unconscious, that's it. You won't be aware of when death happens, which will be very soon thereafter, BTW. N can take from 1 to 2 hours. CO is minutes.
BUT, the one thing about CO is that you DON'T want to screw it up. If you screw up and don't die, you WILL be physically damaged, most likely to the point of not being able to even try and end your NEW FOUND MISERY ever again. It needs to be a one and done. It has to be right the first time.
