Pediatrics Vol. 121 No. 6 June 1, 2008 pp. 1213 -1224 (doi: 10.1542/peds.2007-2281) 01-Jun-2008 
The “what if” argument: But what if even one child, wearing a non-CSA, non-hockey helmet, were to trip and fall and hit their head on the ice and die?
In fact, a very large survey published in 2008 by a California/ Utah/ Kentucky collaborative of medical researchers showed that in the case of falls of less than 1.5 m in vertical height, affecting young children up to five years old, the number of deaths was less than 1 in a million children. This confirms that little kids are made partly of rubber, a well-known fact (and a blessing) to parents.
Well, actually, little kids almost never die of short falls.
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