Safety

It is essential that you think ahead to your own safety before venturing into any cave. Climbing underground and rope work is specialized and dangerous, and mistakes can easily be fatal. It can involve people at moderate levels of fitness yet challenge the endurance of the fittest of athletes. The sights to be seen in caves are seldom seen by human eyes. If you have a serious or chronic medical condition it may be wise to consult a physician before caving. If you go caving, inform your caving companions about your condition before the trip.
Never cave alone. What happens if you trip and break your leg? What happens if you knock yourself unconscious? If you cave alone, you die alone. Contact a local grotto, or someone who has prior caving experience.
Always tell someone where you are going and when you will be back. If your group gets lost, stuck, injured, or somehow lose your lights, how long will it take someone to find you if no one knows where you are? How long will it take your friends or loved ones to realize you're not coming back? Eight hours? Twenty-four hours? Two days? A week?
Always have at least three sources of light. Your primary light source should be a headlamp, mounted on a helmet. Your secondary light can be a regular flashlight, but it should be attached to the side of your helmet as well. The third source can be a mini key ring light (super bright LEDs work well), "glow sticks," candles (good for warmth as well), or another flashlight. Don't forget extra batteries and bulbs!
Always wear a helmet with a chin strap. Even a cheap $10 construction helmet with a chin strap is better than nothing. It's not even falling rocks you need to worry about so much as smacking your head.
Good lug soled boots can ensure safe footing. Your footwear should have good ankle support. Long pants and a warm shirt are a must in potentially cold caves. Gloves will save your hands. Your vertical equipment should be of good quality and well maintained.
Never attempt climbing a pit without proper training. "Knotted ropes" and the "hand-over-hand" technique don't work for climbs over a few feet. Clothesline, cotton rope, twine, or other dubious ropes will kill you. Climbing and caving ropes are designed to withstand the rigors and special problems in caving. There is special equipment which allows you to safely get down your rope, and back up again. This equipment and these techniques take training to use safely.

Never cave while under the influence of drugs or alcohol. Even if you aren't tripping over your feet, drugs and alcohol will impair your judgment, possibly causing you to damage formations, trip and injure yourself, dramatically increase the chances of hypothermia, or make other fatal mistakes. Think twice about caving if you're not feeling well or using medications.
You are responsible for your own safety. There are no phones underground, and even if there were, rescue teams can take too long to reach you. Even with immediate response, the nearest rescue team is likely 6-8 hours away, or more. Learn self-rescue techniques, and make sure you and the members of your group know first aid. Watching a friend die because you don't know how to help is a life-altering event.
A first aid kit is a must for each member of the caving party.