Good evening all, after calling my friend at work today he explained the process to me.
The fg they use is on very large rolls weighing 1ton.
It comes off the passing over a grille with hot water and mild detergent spraying over it.
Then passing over a second grille with clean hot water spraying over it.
Then passing through a heated (75 centigrade) tunnel with fans removing all the moisture, apparently that's most important.
From here it passes over a large cutting table with hydraulic dies that cut the required size and shape to suit whatever they are making.
Then into the laminating room where it is formed and bonded with polyester resin.
Hope that this explains it for those interested.
Basically he said that washing your fg will remove any unwanted surface contamination, and please ensure that all moisture is removed prior to use.