Basic Electrical Installation Work

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8 A trestle scaffold.9. . FIGURE 8.6m must tied the building give them stability. The platform must be at least two boards 450mm wide. MOBILE SCAFFOLD TOWERS Mobile scaffold towers may constructed basic scaffold components or made from light alloy tube.Basic Electrical Installation Work 168 Safety First Scaffold ● scaffold mobile towers are always safer than ladders for working above ground. Trestles which are higher than 3.5m for boards 50mm thick.7 Correct procedure for erecting long extension ladder. The tower built slotting the sections together until the required height reached.5m from the working platform, trestles may not used. The boards which form the working platform should be equal length and not overhang the trestles more than four times their own thickness. TRESTLE SCAFFOLD Figure 8. The maximum span boards between trestles is: ● 1. Two pairs trestles spanned scaf- folding boards provide simple working platform. least one-third the trestle must be above the working platform.8 shows trestle scaffold.3m for boards 40mm thick ● 2. Start position Footing base of ladder Lift and walk towards wall Continue until upright FIGURE 8. scaffold tower shown in Fig. Where anyone can fall more than 4. the platform more than above the ground, toeboards and guardrails must fitted, and separate ladder provided for access. 8