I have to vape each one before I climb in the hole...twice...I'm normally sitting on that little 4 inch I beam, sideways, for about 45 minutes. That's a long go without a vape.
The I beam sits about 18 inches off the ground. If I have issues and it takes longer than 45 minutes I normally have to get someone to come pull me out because my legs fall asleep. Like dead dead.