Table IV. Deep-Ocean Effects on Insulation Resistance of 

 Electrical Insulating Materials 



Materials 



Insulation Resistance (megohms) 



Voltage 



(15 mils thick) 



Before Exposure 1/ 



After Exposure Ij 



Breakdown 3/ 





Exposed in Se 



diment 





Straight Wire 









Polyethylene 



20,100,000 



335,000 



None 



Polyvinyl chloride 



4,400,000 



112,000 



None 



Silicone rubber 



6,200,000 



Insulation destroyed 



Failed 



GR-S rubberi/(SBR) 



5,500,000 



8,300 



None 



Neoprene 



36,000 



7,200 



None 



Coiled Wire 









Polyethylene 



20,100,000 



1,275,000 



None 



Polyvinyl chloride 



4,400,000 



1,250,000 



None 



Silicone rubber 



6,200,000 



Insulation destroyed 



Failed 



GR-S rubber (SBR) 



5,500,000 



830,000 



None 



Neoprene 



36,000 



30,000 



None 





Exposed About 3 Feet Above Sediment 





Straight Wire 









Polyethylene 



20,100,000 



138,000 



None 



Polyvinyl chloride 



4,400,000 



97,000 



None 



Silicone rubber 



6,200,000 



5,200 



None 



GR-S rubber (SBR) 



5,500,000 



3,800 



None 



Neoprene 



36,000 



17 



None 



Coiled Wire 









Polyethylene 



20,100,000 



25,000 



None 



Polyvinyl chloride 



4,400,000 



25,000 



None 



Silicone rubber 



6,200,000 



25,000 



None 



GR-S rubber (SBR) 



5,500,000 



1,700 



None 



Neoprene 



36,000 



16,600 



None 



J/ Average of 8 wires. 



2/ Average of 2 wires. 



2/ Tested at 1,000 volts AC for 



_4/ Government Rubber Styrene 



10 seconds. 

 (75/25 copolymer of butodiene/styrene). 



14 



