I picked up a sheet of polycarbonate a while back to replace the windows in one of my milling machine enclosures. I know polycarbonate isn't as scratch resistant, but it is nearly shatter proof.
Today I finally got around to replacing one of the six panels, and every time I walk into that machine room I am startled for a second thinking I left that door panel in the up position.
I know it will get coated in chips, coolant, oil and scratches soon enough, but its kind of nice to stand there and see clearly the job running.
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I bought this polyester film to repair the insulating window inserts I made in the early 1980's, which have finally become brittle from UV. You could protect the polycarbonate with it.