Acrylic plastic can be damaged by harsh solvents and cleaners. Use a commercial plastic cleaner or mild soap and water to remove dirt and debris. When applying the cleaner, use a non-abrasive lint-free or microfiber cloth that won't scratch the surface.
For tough grease, oil, or tar residue, use commercial grade hexane or kerosene. All solvents need to be wiped clean with fresh water and blotted dry to reduce and prevent water spots.
When cleaning acrylic sheeting, never use ammonia, acetone, carbon tetrachloride, or gasoline as a cleaning solution. These kinds of solvents can cause cracks in acrylic sheeting and give the surface a frosted appearance.