CHICAGO (AP) - ComEd is reminding customers that helium-filled Mylar balloons can cause power outages.
The utility says that so far this year the balloons have caused outages affecting about 11,000 customers. That includes about 900 customers affected by a balloon-related outage on Wednesday.
Mylar ballons have metallic properties that can cause a surge of electricity. A surge can cause the equipment to short-circuit.
ComEd suggests consumers keep balloons tied down at all times and attached to weights.
Also, properly dispose of Mylar balloons by puncturing the balloon to release helium that otherwise could cause it to float away.