Tomas a Prueba de Manipulación

An object touching only one slot cannot open a tamper-resistant receptacle's internal shutters; both must be pressed simultaneously, as a plug does. Required in dwellings from the 2008 edition.

When it applies

Tamper-resistant receptacles are required in nearly all the 15- and 20-amp, 125-volt receptacles you install in dwellings, plus places like child-care centers and waiting rooms. If a little one can reach it, it almost certainly needs the shutters.

Common mistakes

• Grabbing a standard receptacle off the shelf because it was cheaper, then failing inspection.
• Forcing a plug in crooked and cracking the shutter mechanism, so it never seals again.
• Assuming a spot is exempt because it is up high, when the Code still calls for TR.

In the field

I once had a homeowner swear the new outlets were defective because plugs went in harder. I showed her both blades have to push evenly at the same time, and that little bit of resistance is exactly what keeps a hairpin or paperclip out. Once she understood it was protecting her kids, she stopped asking me to swap them.