NBN EN 12811-4:2014

This European Standard specifies product requirements, methods of structural and general design and tests for protection fans for scaffolds to protect workers as well as members of public from objects that may fall off the outside edge of scaffolds being used close to where they are working or passing by.
This European Standard only applies to protection fans while the scaffold is being used as a working place.
Protection fans attached to structures other than scaffolds as defined in EN 12811 1 are outside the scope of this European Standard.
This European Standard applies only to protection fan systems on to which construction debris may fall from 24 m or less.
This European Standard ensures resistance of protection fans for most blunt falling objects representing an impacting energy not exceeding 720 J.
NOTE This energy corresponds to a 3 kg object falling from 24 m.
This European Standard does not cover the requirements for the total area to be protected against falling items.