Years ago, a hoist holding the 700-pound engine and transmission from my Triumph TR3 collapsed and dropped the entire assembly on my foot. Luckily, the oil pan deformed and I got to keep my toes (if in a slightly modified configuration). Since then, I've worn safety-toe boots. The relevant U.S. standard specifies that a safety toe must withstand a 75-foot-pound impact and 2,500 pounds of pressure.
I recommend: Red Wing safety-toe work boots
[Image courtesy FindNSave