Magnetic danger
Some twenty or more years ago light switches were located on a shoulder level of a grownup man. Today they locate it on a groin level, so that kids could reach it.

Some would say, it's just a nonsense of old times. However I remember my grandma not letting me sleep on sofa that was placed in front of outlet in the wall. She said, it's bad for health. Back then, when there were no pc's and mobile phones, just bw tv sets, AM radios, irons, fridges and washing mashines. That was it.

They did not let kids reach the switches intentionally. I actually remember receiving a small electric shocks from those switches as soon, as I could reach them on my tiptoes. Child's body is somehow a much better conductor.

Today some of that philosophy still remains in a few child clinics. They say to switch off mobile phones inside the building. They however sometimes add, that this is not to damage medical equipment or disturb it's function, knowing that nobody will believe magnetic field can be a risk for a living creature.