Hi,

If I understand well, you mean the platform which is permanently mounted on the truck, without the option to remove it.

I never met such solution, excluding some narrow aisle high lift order pickers, where the platform is the operator compartment.

As far as I know, the directives and standards apply only to removable platforms.

Just check the:
EN-1459-3 (I think it still exists as a draft prEN)
FEM 4.006 rev. E 2010.

In case you have the problems to get these, I sent them by mail.

This is all I found about the forklifts platforms application.