OSHA general industry standards that broadly deal with personal protective equipment (PPE) can be found under 29 CFR 1910.132-138. 1910.136 specifically addresses foot protection, and portions of the more general 1910.132 are also applicable to foot safety. These standards require that you assess the need for particular PPE items, including safety footwear, throughout your facility. This is best accomplished by evaluating each job task, as opposed to merely considering general occupational functions.
The majority of OSHA citations regarding foot protection call for ANSI-approved safety-toed footwear. Approval is tied to the ability to resist compression and impact. The safety toes are commonly made of steel, but a new composite material has been approved. Employees may balk at wearing the shoes, complaining that they will be uncomfortable. But with the correct fit and suitable socks, there shouldn't be any significant problem. ANSI-approved foot guards can be worn over conventional footwear, but special diligence must be used to ensure that there are no attendant tripping hazards.