Hi Alan

I have used International Interdeck successfully on a wheelchair ramp and can recommend it, but, if all you are wanting is a small area on the floor of a GP, it would be an expensive answer.  Ordinary paint or varnish, dusted with dry sand before it dries will give perfectly satisfactory results.  Try to get a gritty sand, preferably sieved to ensure consistent particle size.

Good luck

Norman

Or if you are concerned about weight, a coarse granulated sugar will do the job as well. It won’t dissolve in the paint if it’s oil-based, but it will dissolve in water, leaving a rough surface. Less hard-wearing than sand, but gets the job done. You can also get sandpaper-like strips to stick in areas of the floor where you’re likely to be treading, which is what I had on my Mirror.

This stuff is brill – https://www.teamac.co.uk/products/category/deck-paints/suregrip-anti-slip-deck-paint