More common, though still infrequently, Mr. Doyle said engineers notice an unusual bump or hitch in the rails as they drive along, and flag a potential problem before it can cause an accident.

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Human error is the most likely cause of an accident.

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But just one diarrhea accident can cause an infection for anyone who gets a mouth full of pool water.

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His family do not believe he shot himself and think horseplay or an accident could have been the cause.

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Officers were trying to determine the cause of the blaze, which wasn't the result of an accident.

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However, most kidney tumors these days are found not because they cause symptoms, but are spotted by accident when people are having an X-ray or other imaging test for something else, like back trouble or chest pain.

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Although larger ships would cause more environmental damage and create an enormous rescue challenge in case of an accident, they also offer greater comfort and more amenities.

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The fire is now 25 percent contained and the cause hasn't been determined, though investigators are looking into whether it was lightning, an accident or arson.

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