Plumbers install, repair and maintain pipes, fixtures and other plumbing equipment used for water distribution and waste water disposal in residential, commercial and industrial buildings.

管道工安装，维修和保养管道，装置和用于住宅，商业和工业建筑的配水和废水处理等水暖器材。

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Many people could not get jobs because they struggled to read graphs and interpret documents, while plumbers unable to do the calculations required to install an energy-efficient boiler might lose income, he suggested.

BBC: Poor numeracy 'blights the economy and ruins lives'