丈量員主要負責以下職務 - (a) 協助測量主任或土地測量師職系人員進行實地測量工作; (b) 在進行實地測量工作時，預備、運送及維修各種測量儀器、工具及物料; (c) 保持測量物品倉的整齊和清潔; (d) 協助訓練二級工人；以及 (e) 按指示履行辦公室雜務。 (註：丈量員或須不定時工作和超時工作及在香港任何地方工作和暫住。)

A Chainman is mainly deployed on - (a) assisting members of the Survey Officer or Land Surveyor Grades to carry out survey work in the field; (b) undertaking the preparation, transportation and maintenance of survey equipment, tools and materials for field survey operations; (c) maintaining the order and cleanliness of the survey store; (d) assisting in training Workmen II; and (e) performing other office duties as instructed. (Note: Chainman may be required to work irregular hours, overtime and work and camp in any part of the territory.)