1 Scope
This part of BS 1139 specifies requirements for the structural design of prefabricated tower scaffolds utilizing components from mobile access and working towers specified in BS EN 1004‑1 but in configurations that are outside of the scope of that standard.
These configurations include:
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a)
high level tower scaffolds outside the maximum height limits of BS EN 1004‑1;
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b) tower scaffolds with more than one working platform at one time;
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c)
large deck tower scaffolds;
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d)
linked tower scaffolds;
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e)
cantilever tower scaffolds;
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f)
stepped tower scaffolds;
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g) tower scaffolds used as a means of access to another place;
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h) non-mobile towers built on base plates instead of castors; and
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i) tower scaffolds subject to wind loads greater than 0.1 kN/m2.
NOTE Towers with wind loads up to 0.1 kN/m2 are specified in BS EN 1004‑1. Where a prefabricated tower scaffold might be subject to wind in excess of 0.1 kN/m2, and it cannot be dismantled or moved to avoid these winds, suitable wind design
criteria can be found in this British Standard.
This British Standard does not cover prefabricated tower scaffolds using guys as a method of stabilization.
This British Standard does not cover prefabricated towers intended to be lifted.