నిచ్చెన: కూర్పుల మధ్య తేడాలు

 

==బయటి లింకులు==

* [http://firstaid.about.com/od/injuriesathome/qt/06_ladders.htm Ladder Safety] including Ladder Types (Type I, Type II, Type III)

* [http://www.builderbill-diy-help.com/ladders.html Ladder Usage] Safety and handling ladders