Well, for this question, I think the most important thing you should do is to clean them carefully. For example, the manufacturer of the safety glasses will have precise instructions on how to effectively use their particular brand of safety glasses and in the instructions, you can also learn how to clean them. So you should read the instructions carefully. And then just do it in a right way. Besides, you also should remember that as every model of safety glasses are rated differently, the rating should be adequate for the task being performed. Finally, you'd better know that you may need to change safety glasses in accordance with changing duties. So that it can protect your eyes.