1. Acetylene explosion (acetylene still used by some as fuel for cave lamps) 
  2. Camp stove explosion (white gas or butane) 
  3. Fall while climbing rock 
  4. Fall while downclimbing rock 
  5. Fall while ascending rope 
  6. Fall while rappelling (descending rope) 
  7. Rockfall 
  8. Dig or tunnel collapse 
  9. Unplanned detachment from rebelay 
  10. Failure to complete change from rappel to ascent, and vice versa 
  11. Prusik knots jammed 
  12. Prusik knots won’t grip 
  13. Ascenders slip on muddy, wet, or icy rope (this one almost got me on a 250-foot drop) 
  14. Strangulation in vertical gear 
  15. Fall from losing grip on handline 
  16. Rope anchor failure 
  17. Rope failure 
  18. Rope cut by falling rock 
  19. Ladder failure 
  20. Uncontrolled rappel 
  21. Harness carabiner opens during rappel (as with Chris Yeager) 
  22. Rappel shunt (emergency brake) defeated during rappel 
  23. Unwanted rappel shunt activation 
  24. Rappel off end of rope (as with Alexander Karabikhin)  
  25. Drop rope 
  26. Rope recoils out of reach after rappel 
  27. Rappel into pit without ascent gear 
  28. Foot hang 
  29. Chemical contamination of rope 
  30. Animals eat rope 
  31. Rappel rack nut falls off 
  32. Hair caught in rappel rack 
  33. Clothing or chinstrap caught in rappel rack 
  34. Sewn sling tears 
  35. Exhaustion 
  36. Hypothermia 
  37. Drowning 
  38. Becoming lost 
  39. Out of light 
  40. Entrapment by flood 
  41. Entrapment by rockfall 
  42. Asphyxiation by methane, carbon dioxide, blast fumes, etc. 
  43. Locked inside gated entrance 
  44. Poisonous snakes and insects 
  45. Cave stream 
  46. Struck by lightning while talking on cable telephone to surface 
  47. Rabid bat bite 
  48. Bacterial or fungal infection:  histoplasmosis, etc. 
  49. Hyperthermia  (some caves are 130F)  
  50. Incapacitating injury 
  51. Incapacitating illness 
  52. Stuck in crevice

James Tabor