It is not a hard and fast rule that you can not bring your lights. I know - I am a safety diver at the mine. If you have never been diving at the mine, we have mapped out "trails". Trail #1 is the first (obviously), and a portion of it is a checkout dive. We are extremely safety conscious, so we check basic skills right off, making sure you can clear your mask (if it floods), and buddy breathe. These are basic skills ANY diver should be able to do, and we want to make sure you can do them for your safety, as well as that of others. After all, these are group dives, and while we want to have FUN, we also want to be safe. There IS a rule about no lights on Trail #1. After that, lights are at the tour guide's discretion - some are OK with lights, others not). Here is the concern with lights: the tour guide and safeties use light to signal to one another, as well as signal to other tourist divers, and gain their attention (e.g. - The tour guide can signal the safety, asking if all is OK, and I can signal back whether things are OK or not. Also, if the dive profile for our trail is say 50 feet for the max planned depth (for a 45 - 50 minute dive!), and a dive tourist is dropping to 80 feet, the tour guide would signal you to come-up to level with the rest of the group!). It can get really confusing, really quickly, if everyone is utilizing lights! The tour guide also uses a light to highlight and show items of interest along the way. Other lights can be a distraction. A HUGE problem with dive tourists with lights on a group dive, is when the tourist forgets to turn the light off, when not in use, and just let's it hang free, and bounce around on a lanyard (seems to happen no matter how many times we might request that folks be kind enough NOT to do this on a dive, it still happens!). If you are one of the unfortunate people diving below or behind someone with a dangling, bright light, inadvertently left on, you would understand the problem (you are continuously flashed in the eyes with the light). Anyway, I wanted to provide a few more FACTS about the light rules. I hope it makes sense now. One other thing: there are POWERFUL, sodium, stadium lights above the entire lake. The visibility is 100 feet, plus. It's amazing. With no lights, being down 60 feet, you can easily see everyone and everything around you, without the need of a light! IT'S AWESOME, and amazes everyone who experience it for the first time (no, it's not dark and pitch black like a cave. most of the environment we dive is completely open water. if we go uder any overhead, it's for a VERY short duration, in and out usually, and there is always more than one way in or out, and you can ALWAYS see light from either entrance or exit! We are typically talking going under big, huge, open archways!). I hope you can come down and join us for some dives. It truly is one of the most awesome places you will ever dive. The water is a constant 58 degrees, year round. I dive a wetsuit, and make several dives a day performing safety duties. I, myself, have no issue with diving the mine in a wetsuit (I'm 51 years old). There are lots of staff who dive in drysuits, and claim to be a lot more comfortable! Anyway, if you have any questions or anything, you can call West End Diving for more information, as the dive shop also runs the Bonne Terre Mine dive operation (Doug & Cathy Goergens are the owners of West End Diving, run the diver operation at the mine, and also have a dive resort called Maya Palms, down in Mexico. West End Diving's number is (314) 209-7200). Hope to see you down at the mine!