I resumed my earlier charcoal briq tests today and was successful, the result being that in a 10 cubic meter room, to achieve 10000ppm of CO saturation, 5-10 kgs of charcoal briqs are sufficient, I cannot offer you any less than that ;)
I used 500 grams of supermarket briqs, which I set aflame with a special setup that would guarantee their equal burning (NOT a bleeding chimney starter), this took 20 minutes. After 25 minutes, I removed the now 2/3rd grey briqs into a more room-compatible aluminum receptacle (careful, this stuff is extremely hot) while some of them were still burning with very low flames, changing over to glow-state, and carried them into the sealed bathroom with the CO meter.
The first alarm came after 7 minutes and showed 330ppm, the second after 12 with 530ppm, the third a bit later with 570ppm - the meter, to my surprise, doesn't go any higher... that was my top level reached in a test last week but it also seems the hardware limit of this gadget. Sigh. Got it from Amazon.
My conclusion below - the meter had been placed close to the wall, a yard from and higher than the CO source. I had to open the door three times, thereby each time diminishing the CO concentration by about 15%... the CO concentration will normally not be diminished but steadily rise, and when I broke off after 25 minutes, target reached, the coals hadn't even started to disintegrate.
On the whole, it can be assumed that [you get 570ppm from 0.5kgs in 10 cubic meters, you will get 1140ppm from 1 kg, times ten to get 11400ppm] so given the losses I consciously tolerated, 0.5 to 1 kg of charcoal/briq matter set alight correctly and equally and employed with discipline, would create a fast-killing climate in one cubic meter of air inside a closed room, tent or car but I wouldn't use one of the latter two for fear of fast dissipation - also, the heat is intense and doesn't go well with the plastics cars and tents consist of these days. I almost burned a perfectly good IKEA chair which I had insulated with several layers of aluminum foil - not enough.
You would stay inside this room and the coals would go on giving off CO for the next half hour (couldn't wait, had to walk the dog), accumulating inside your sealed environment.
You may not like my way of using a cheap CO meter but the method is perfectly scientific, and I had been running some preemptive testing last week the results of which are corroborative to my results of today.
Next will be another acid test ;)
