I've read some posts in other threads that 30 ml equal's 1 carton
If that is true I am vaping too much
It truly is individualized based on variables too numerous to mention, but ~4mL (+/- 1mL) at 18mg nicotine is the widely accepted "norm" for a 1-pack-a-day "light cigarette" smoker (the national "average smoker").
...so ~40mL (+/- 10mL) would be equivalent to a carton of cigarettes ...on average.
I'm an ex PAD smoker and I'll easily kill 5ml a day, however, I am allowed to vape non stop at work, and I am a definite chain vapor so it goes quick