Updating 2 prong electrical outlets
If this DIDN'T occur, anyone who touched the box or housing would get a shock - whether you've got a GFCI outlet is irrelevant.
A GFCI outlet protects against a short (or more commonly a current leakage) involving YOU and an electrical device plugged into the outlet.
However, they should never be used in areas where I recommend GFCI's.
In those areas, they are particularly dangerous and should be replaced with grounded GFCI's.
Not ungrounded outlets need to be upgraded, so let's go over (in detail) the options you have in upgrading ungrounded outlets.
Let's start off by distinguishing an ungrounded outlet from a grounded outlet.
You see, most residential outlets are designed to handle up to 120 volts of electricity.I've read that as an alternate to re-wiring your entire house to get more protection (and a 3-prong adapter) at your outlets, you can safely (and under code) just replace each outlet with a GFCI outlet (or a central GFCI, I suppose). What level of safety does it provide using a GFCI on an ungrounded circuit versus a grounded circuit?A GFCI and a grounded outlet do two different things and protect against two different scenarios, and one is not a replacement for the other.As far as buildings codes in the US go, the only acceptable way to replace a two-prong outlet with a three-prong outlet in an ungrounded circuit is a GFCI outlet.I wouldn't use them for every outlet if the entire house is ungrounded, though.