Solution: Replace two-prong receptacles with properly grounded three-prong ones, if wiring allows it (see . Plug Falls Out of Receptacle What it means: Worn contacts in receptacle no longer grip the prongs firmly. (A new one costs about .) Many homeowners feel comfortable doing this themselves.
For older, unmarked fixtures, use only 60-watt bulbs or smaller. Danger level: Minimal, as long as wires aren't within reach. Aside from the annoyance, the frayed wiring can arc and start a fire.
Caveats: Cannot be grounded or spliced into a grounded circuit.
Its soldered connections may melt if too much current flows through them.
This is a simple job that many homeowners do themselves. (There will likely be a minimum job charge.) Note: As an alternative, GFCI breakers () can be installed on the main panel.
But then every time one trips, you have to go down to the basement to reset it. It may become an issue when the house is being sold and an inspector looks inside the panel. Aluminum corrodes when in contact with copper, so connections loosen, which can lead to arcing and fires.