Mateusz Konieczny
I would consider documenting it at OSM Wiki - https://wiki.openstreetmap.org/w/index.php?search=Tag%3Abarrier%3Dbarrier_board&title=Special%3ASearch&profile=default&fulltext=1 is not existing

Though what I found at https://commons.wikimedia.org/wiki/Category:Zeichen_600 is either temporary and/or mappable as a fence like https://commons.wikimedia.org/wiki/File:Wuppertal,_NBT,_Treppe_Montagstra%C3%9Fe,_oberer_Abschnitt,_Abgangssperre.jpg