1. BSI. BS 5973: 1993: Code of practice for access and working scaffolds and special scaffold structures in steel.1993, BSI, London, UK.
2. BSI. BS EN 12811-1: 2003: Temporary works equipment. Part 1: Scaffolds. Performance requirements and general design.2003, BSI, London, UK.
3. NASC (National Access and Scaffolding Confederation). TG20:05 Guide to good practice for scaffolding with tubes and fittings.2005, NASC, London, UK.
4. NASC. TG20:08 Guide to good practice for scaffolding with tubes and fittings.2008, NASC, London, UK.