Likely Cause: Hydrogen Combustion

Hydrogen Combustion

H2 + ½ O2 H2O +Energy Ignition Source

H2 Flammability Limit: 4% in air H2 Detonation Limit: 18% in air

Hydrogen Production via Copper Corrosion

Electrochemical Reaction Anode: Corroding Cathode: Protected from Corrosion

Cu+2

H

e- Copper (Cu)

e-

H

H+ H+

H2

Beach Schematic

Air

Sand and Water Wire

Corrosion Zone: H2 Buildup

H2

O2

H2O

O2 Diffusion Zone

H2 + ½ O2 H2O +Energy

Combustion Zone

Sand and Air

H2

H2

O2

O2

Cable End Differences

Up-Slope End: Corroded End Near Event: No Corrosion

Hydrogen Flame Properties

Very low ignition energy

Flames not visible

Flames radiate very little heat

Observations & Conclusions

No flames observed

No burns

No explosive residues

Methane levels below or near detection

Likely source of hydrogen identified in close proximity to explosion

Flammable hydrogen levels detected in beach sand : Values up to approximately 5% of air pressure

Conclusion:

All of the above consistent with a hydrogen combustion.

Removal of wire and aeration of sand make future combustion unlikely.

GSO Participants

Prof. Arthur Spivack

Prof. John King

Prof. Brian Heikes

Justine Sauvage

Kira Homola

Dennis Graham