Back in 2014 I got certified to scuba dive. It's probably the most rewarding cert in my wallet.
During training, I learned all about decompression sickness and how carbon monoxide in smokers increases the risk. Sounded horrible; everything from veins imploding to death. Haven't smoked since. Cigarettes, of course. = }
But they're on my mind regularly so smoke one for me!
Will pull out my pipe and enjoy fresh just for you! Cannot implode, explode or anything else any quicker with the filth around.