Charged raindrops can degrade protective coatings and metal, study finds

The short version

• A study cited by Jalopnik found that raindrops can accumulate upwards of 9,000 volts of static electricity as they slide over insulated surfaces.[Jalopnik]
• When charged salty droplets discharged on Teflon-coated copper at a 50-degree angle, microscopic tests revealed structural defects piercing both the coating and the metal.[Jalopnik]
• Initial tests at a 10-degree angle caused no damage, and droplets falling onto non-conductive materials did not trigger corrosion.[Jalopnik]

Key facts

• A study found that water droplets can collect upwards of 9,000 volts through charge exchange and contribute to surface corrosion.[Jalopnik]
• Tests exposing a Teflon-coated copper sample to 3,000 salty droplets at a 10-degree angle caused no visible damage.[Jalopnik]
• Tests conducted at a 50-degree angle across four insulated surfaces produced defects penetrating both the Teflon film and the copper substrate.[Jalopnik]
• Droplets landing directly on non-conductive materials showed no corrosion defects during testing.[Jalopnik]

Sources

Outlet counts describe coverage, not independent confirmation. Reports may share a wire service or original source.

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