Bryan,
I think that my post has fallen foul of the PC police.
The common usage of the word for the waste product of a furnace cannot now be used.
You are correct in what you say about our childhoods, even though mine was in the 50s and 60s.
Playing around heavy industry, and then there was the scrapyards with old engines and pre war cars.
The worst injury I sustained was a grazed knee, none of my mates ever hurt themselves because we used common sense.
The death's and serious injuries came when we were old enough to legally ride bikes
But that's another story.
Regards
Richard