How to lock a part?

I have a model that I want to be standarised and want nootherpeople can change it when they access it.

I know if I make a part from assembly, it will change intoimportedand not be able to change but how can I lock a model in apartfile? Is there any way I can lock dimension or not be abletoadd/remove anything? Can I put a password?SolidworksParts And Features