I have some but not much experience, and no academic knowledge.
I think it depends on the details. How many instances of the stamped
number are on each piece of tubing? If the tubing is one foot long
it might be one or two, but if it's 10 feet long, 10 or 20. How many
pieces of tubing.
I'd guess, guess, that it takes about as much acetone to remove one
finger's worth of nail polish as one instance of the number and girls
do 10 fingers at a time. OTOH do they use Q-tips, which hold a lot
less than a cotton swab? I forget. It's been 30 years since I had a
girlfriend who used to remove her nailpolish, it seemed like every
day, in front of me.
When I use acetone, I close the bottle as soon as I wet the cotton,
because it will evaporate right out of the bottle, and so I won't
spill it. Does he do that? I think I would have him keep his
bottle, esp. when it's open, in something like a dishpan, the kind of
rubber pan as big as two loaves of whiite bread side by side. Then
if he spills it, he can take the whole pan outside, pour as much as he
can back in t he bottle and spill the rest on the ground., I have
used dishpans this way.
Maybe he can put the tubing in there when he's done with it and have
it rest outside too, although there may be no point to that . The
acetone probably has evaporated within a minute, so there is nothing
to dry. .
Maybe for the whole project he could go his bedroom and close the door
and open the window for the 15? minutes it takes to do all this? If
you don't smell it in the rest of the house, you'll know it's not
getting there. He could do it on the bed with a dishpan to hold the
bottle of acetone. Check a part of the pan to see if acetone
dissolves.
Although of course if you do smell it and stop smelling it, it may
well only mean your nose sensor for that smell is tired. How long
does it take until a nose stops sensing a smell, 15 minutes? Isn't
that why a person doesn't know when he has bad breath or body odor?