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i was pointedly being really simple , there really is no point in "P.E."

engineering in a hoist to unload a 1/2 or 1 ton pick up , some basics
will get you all the way home , while 1.67 is a standard in A.I.S.C.
work , there is not a crane, hoist or any other lifting device built
using that small of a safety factor , as shifting or otherwise unstable
load can load that system well over its rated factor very quick .

example would be an overhead crane rated for 70 tons is built to
a safety factor of four . and i have personally seen a 35 ton injection
mold break an eye bolt and bring the whole thing to the floor .


safer is heavier and more expensive