No, you could not share it. Because it may cause transmittable skin and other diseases. If it is urgent or you need to shave but the shaving tool is not available then you can share it. The only thing that could be bad is if the trimmer has been used on broken skin or open sores and on someone with a bacterial scalp condition. You can get a disinfectant spray for the blades. If used on clean and healthy skin it is perfectly safe. Give the clipper or trimmer a good scrub on the blades with a coarse nail brush to remove residual hair. Wash it with hot water and use it.