is the outlet grounded and is the thing you wish to plug in grounded also? They make a big thing about hot/neutral and it was all about putting your finger into a light bulb socket and having the shell hot instead of the grounded neutral. BUT they still put polarized cords on toaster and mixers too. Not necessary. Years ago ( a lot of years ago) they used a , what they called a hot (or chicago) three way which switched the hot/neutral every time you turned on the light. I don't remember people dropping like flys. Every house built before the fiftys had it. Don't put your finger into the socket and you'll be just fine.