How can you tell if a cave is safe to enter?

Answer 1

There is an important difference between Risk & hazard. Caves present objective hazards but the risk of them causing an accident, and the potential severity of the outcome is far more subjective and difficult to assess. It depends greatly on the cave and natural conditions, and even mmore so, on the individual at the time.

Judging by cave rescue organisation annual reports and by personal experience....

Falling off a climb or even slipping off a boulder - the most common hazard and greatest risk.

Falls due to equipment failure: very rare. Modern caving equipment is subject to stringent quality regulations, and any kit failure now is almost certainly due to poor use, poor maintenance or neglect.

Water and cold: drowning, hypothermia. Modern techniques and clothing are designed to minimise the risk, particularly by rigging pitches (vertical drops) clear of the waterfall. It won't account for cavers themselves misjudging the obstacle and being over-confident in trying, for example, to swim across deep pools without suitable clothing and bouyancy aids.

Floods: if the water does not drown you the cold might kill you if you are trapped in a dry passage but beyond the flooded section. Avoided by knowing as much as possible about the chosen cave and its area, and not going down floo-prone caves when the weather is wet or mayy become so. It is very sobering to stand outside a cave and see silt on the trees some fifty feet above the entrance itself...

Lost: yes, cavers occasionally do become lost in complex systems, though it's not very common. Avoided by care, taking a copy of the survey or description and looking at the ladmarks as you go. No, in case you are wondering, you DO NOT mark the junctions with arrows etc on the walls, though small, temporary cairns you remove on exit may be permissable with consideration for the cave and other cavers. Nor, with one exception, do you use guide-string - unless you are a cave-diver... in which case you would not have asked. The exception is laying a guide-line to mark the safest route through a boulder-choke...

Which brings us to -

Things falling on you. It can happen but is rare. A greater hazard is movement or collapse of unstable boulders or loose slopes. Having said that, I recall reading of an American caver struck and injured in the vertical shaft entrance of one cave, by, of all things, a falling racoon!

Lastly and most importantly... YOU! Your physical and mental ability on the day, the care you take of your equipment and of yourself, your knowledge of the cave and weather conditions, and so on.

Answer 2

You could take a flashlight or listen for and sudden noises