It has been stated often you can't put items on the ground!
How about camera tripods? Is there some kind of sheet you can bring along to stop the contact?
Also - my most comfortable walking boots have steel toe caps. Are they a problem?

Just ask the guide if it is safe to put your tripod on that paticular spot. In most places it is complitely safe, but there are some "hot spots" where you better not put anything. The guides know about those places and will tell you where you should not step. Just follow the instructions, and your equipment will pass the radiation control without any problems

Thank you!