Our deparment used an indoor range frequently and we were often there for a week at a time. I also shot at least one IPSC match per week there and sometimes an IDPA or bowling pin match. My lead got up to 26 at the time which was 8-10 years ago. I left that dept and ended up at one that uses an outdoor range so we don't see the indoor more than a few times per year and I no longer shoot matches on the indoor range. Last check about a year ago it was 10. My training partner spent at least as much time as I did and continued to shoot the indoor matches and he lead level last year got up over 40 and he was taken off the range staff for about 6-10 months. He did get the level down around 25 in that time.
Its a real pain but here's what we're doing to cut down exposure as much as we can:
Absolutely no drinks/food taken into the indoor range. We keep ours in a classroom outside the shooting area. We don't even chew gum when we're in there.
If you leave the range area, wash your hands, as described above before you do ANYTHING to include going to the restroom. Especially if you are going to eat, drink or smoke.
If you must pick up brass or things off the floor, have a pair of gloves that are kept in a plastic bag and used only for that purpose. Whatever you pick up off the floor has some too so keep that in mind when you're loading. (see below)
Keep a change of shoes in your vehicle and change them before getting in the vehicle and put the range shotes in a sealed container like a tupperware container. Don't wear them home or go in the house with them as whatever was on the floor of the range goes home with you. If you have small kids crawling or playing on the floor, guess who gets the aftermath.
Change clothes as soon as you can after leaving the range and wash them separately from other clothing.
We've not had any issues on the outdoor ranges but the handwashing thing should follow you anytime you shoot.
I no longer keep anything to drink (or eat) in my reloading area. When you pour shot into the hopper there's a little dust that floats out. Probably the coating on the shot but if it was on the shot then comes off, it was in contact with lead and I'm not taking chances.
That's our experience so far.