SAN FRANCISCO (KGO) -- BART believes powerful magnets will help solve a mysterious problem that once again delayed commuters last week.
Power surges knocked 22 cars out of service in the East Bay on Friday.
BART blames the problem on metallic dust. Those tiny bits of metal get whipped up when crews grind the tracks and smooth the rails to reduce the noise that trains make.
The dust can conduct electricity and cause trains to malfunction.
"So now the staff has figured out a way to both grind the tracks to get rid of the noise and get rid of the particles so it doesn't cause a propulsion problem for us," BART Board of Directors member Joel Keller said.
BART expects to install the magnets on special maintenance trains in about a month.
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