Do I need to wear safety spectacles under your face shield?
Yes, applicable Standards including NFPA 70E require safety glasses/spectacles to be worn as primary eye protection. An arc-rated face shield or suit hood is designed to protect your face. Both safety glasses and arc-rated protection is required when an arc flash incident is likely to occur.
The ANSI Z87.1 standard covers industrial eye and face protective devices and their use in the marketplace. It defines safety glasses and safety/cover goggles as primary eye protective devises. Their job is to protect your eyes! A face shield is defined as a secondary protective device, requiring the use of a primary protective device underneath. The standard envisions the face shield protecting the face, even though your eyes are a part of your face.