A minimum 3-board working system, along with a single guardrail, is in location when the scaffold is constructed or dismantled. http://[email protected]/info.php?a%5B%5D=werner+scaffolding+%28%3Ca+href%3Dhttps%3A%2F%2Fwww.webwiki.ch%2F%3EClick+at+Webwiki%3C%copyright%3E%29%3Cmeta+http-equiv%3Drefresh+content%3D0%3Burl%3Dhttps%3A%2F%2Fwww.webwiki.ch%2Fhollowayscaffolding.co.uk+%2F%3E