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Purification-plant repair and maintenance work |
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Heating-plant repair and maintenance work |
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Plant upgrade work |
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Roof works and other special trade construction works |
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Erection and related works of roof frames and coverings |
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Roof-framing work |
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Roof-covering and roof-painting work |
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Roof-covering work |
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Roof-tiling work |
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Roof-slating work |
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