The point may be being missed a little here.
Edge protection systems is dealt with specifically in BS EN 13374:2004
The requirement for edge protection in scaffolding on open edge steelwork is shown in the NASC document SG 20.
I do not believe there is a specified dimension from the edge as suggested in an earlier post although there is a note in SG20 stating that the horizontal gap between the puncheon and the edge of the roof or floor must be a kept to a minimum to prevent persons falling.
At no point do I see mention or inclusion in the sketches of a toe board.
The inclusion of the toe board is in essence to make it possible to keep the opening between rails to a maximum of 470mm
If you look to BS EN 13374:2004 which covers Edge Protection SYSTEMS, this however refers to toe boards as a requirement
"3.1 edge protection system
set of components intended to protect people from falling to a lower level and to retain materials, see Figure 1"
All items in Fig 1 show the inclusion of toe boards!
However
"4.1 Class A
Class A protection provides resistance to static loads only, based on the requirements to:
support a person leaning on the protection or provide a handhold when walking beside it; and arrest a person who is walking or falling towards the protection."
Note no mention of falling materials!
Whilst this is an extensive document I will skip to
"5 Requirements
5.1 General
5.1.1 Basic requirements
An edge protection system shall comprise at least a principal guardrail and an intermediate guardrail or intermediate
protection, and it shall be possible to attach a toeboard.
NOTE It is important that components have a surface and be so located that injury to a person from puncturing or lacerating the skin is minimised.
For me this section I have highlighted in red indicates toe board to be an optional extra and as such not a standard inclusion. (not sure all would agree with me)
However where it is included
"5.1.4 Toeboard
The upper edge of the toeboard shall be at least 150 mm above the working surface. see Figures 4 and 5.
The toeboard should be designed to avoid gaps between it and the working surface on normally a flat working surface. If there are gaps, a sphere with a diameter of 20 mm shall not pass through them."
As with most of these documents they are ambiguous and open to interpretation as such I treat them like the rules of golf and interpret them to suit the tree I find myself behind.
If you are behind the tree try the reasoning but be prepared for your opponent to have a different take on the matter, at which time you agree to disagree or take the drop under penalty.
Good luck with this.
If you need further documents to reference PM me your mail address I will respond accordingly
regards
Alan