sentences:  Potential differences between pool water and railings, or shower facilities and grounded drain pipes are not uncommon as a result of neutral to earth voltages (NEV), and can be a major nuisance, but are usually not life-threatening.However, contact voltage resulting from damaged insulation on a current carrying conductor can be very dangerous, and can lead to shock or electrocution.Such a condition can arise spontaneously from mechanical, thermal, or chemical stress on insulation materials, or from unintentional damage from digging activity, freeze-frost seizing, corrosion and collapse of conduit, or even workmanship issues.