From the US Army Corp of Engineers:
Loads on Ice Required Minimum Ice Thickness in inches - Description of Safe Moving Load
1 3/4" One person on skies
2" One person on foot or skates
3" One snowmobile
3" A group of people walking single file
7" A single passenger automobile
8" A 2-1/2 ton truck
9" A 3-1/2 ton truck
10" A 7 to 8 ton truck
More info on their web site, ice safety, links to Ice Load graphs and more - click here.
Ice Thickness and Strength
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