Baby-proofing your homes electrical outlets routinely consists of placing plastic covers or inserts over or into your electric socket plug inlets. Now the new sections of the electrical code require new homes to have tamper-resistant receptacles, designed to prevent children from inserting objects into receptacles.

Denyse Boxell of Safe Kids Canada says is this Canadian Press article [opens in new window]
“The great thing is that finally we have some technology that’s actually passive – it doesn’t rely on the parent to actually make sure that there’s any covers in place,”
However mandating that all receptacles to be installed in any residential home during new work or repair be tamper-resistant receptacles would be a greater and more complete solution for child safety.
How do they work?
Tamper-resistant receptacles have built-in shutter systems that prevent foreign objects from touching electrically live components when they’re inserted into the slots
For a detaled overview of the issue see this link at Electrical Construction & Maintenance (EC&M) magazine [opens in new window]