In total agreement with Ian P
I have been involved with designing, installing and training staff to operate "caving" attractions in Activity Centres, Council Sports Centres etc for some years
If it is a man-made, indoor structure then it comes under all the standard building rules:- emergency lighting, evacuation procedure, air circulation etc.
This can be done with `pop open` hatches, LED lighting etc.
Staff (typically teenage non-cavers) are trained to brief youngsters, lead them through some sections, let them explore for themselves at times, sweep the system if the fire alarm goes off etc.
This is not intended as a substitute for caving, it is a fun experience for kids, trying something they would otherwise never get the change to experience.
I do know of a kid`s activity centre that will put 10,000 youngsters through their system every year, almost all have a great experience.
I agree this NOT an artificial cave, it is a maze, usually fibre-glass / plywood, but we always struggle for a suitable name.
I know I am leaving myself wide open to abuse here; but perhaps someone on this thread can come up with a better name.