Ok, looks like you want to protect your eyes from something else, and you want to use your oakley sunglasses to protect your eyes. So,as you can see, in theory, those sunglasses could fight against some wind or lights. But in practice, they could not fully cover your eyes so it could not well protect your eyes such as sand or something. Anyway, there are some cheap safety glasses on the internet, which could give you what you want. Here is a link for you
It is not ok for you to take the oakley sunglasses as safety glasses. The oakley sunglasses own the protection for your eyes from the uv rays and bad lights. However, the safety glass is a type of glass. Its main role is to resist breaking. Even if it is broken, it will minimize the risk of injuries in the event. The common use of safety glasses is the car windows and so on which will promote safety in collisions. Our regular house windows, eyeglasses, laboratory glassware and so on can also use such type of glasses. However, the common glass can not withstand the forces which are exerted on it. The oakley sunglasses belong to the common material which will not bear such great strength. Then you should not use the oakley sunglasses as safety glasses.