Solo caving is dangerous. If you were hurt there would be no one to go for help.
Caves are dark.
Without light you cannot see you hand in front of your face. If you were to run out of light it would be nearly impossible to navigate out of a cave. Do not try to feel your way out of the cave because you could easily fall and get badly hurt. You will realize how important this rule is the first time you try to stand upright in a five foot high passage. The helmet will also give limited protection against any falling rocks.