ISO 17123-7:20 05规定了在确定和评估建筑和测量中使用的光学管道仪器及其辅助设备的精度（重复性）时应采用的现场程序。ISO 17123-7:20 05不适用于作为tribrachs或测量仪器中设备的光学垂直下降。首先，这些测试旨在现场验证特定仪器是否适合手头的直接任务，并满足其他标准的要求。它们不是作为性质更全面的验收或性能评估的测试提出的。 ISO 17123-7:20 05可以被认为是评估测量（更具体地说是被测物）不确定度过程中的第一步之一。测量结果的不确定性取决于许多因素。其中包括:重复性、再现性（日间重复性）和对所有可能误差源的彻底评估，如ISO测量不确定度表达指南(GUM)所规定的。 这些现场程序是专门为现场应用而开发的，不需要特殊的辅助设备，旨在最大限度地减少大气影响和光学管道仪器调整不完善的影响。

ISO 17123-7:2005 specifies field procedures to be adopted when determining and evaluating the precision (repeatability) of optical plumbing instruments and their ancillary equipment, when used in building and surveying measurements. ISO 17123-7:2005 is not applicable to optical plummets as a device in tribrachs or in surveying instruments. Primarily, these tests are intended to be field verifications of the suitability of a particular instrument for the immediate task at hand and to satisfy the requirements of other standards. They are not proposed as tests for acceptance or performance evaluations that are more comprehensive in nature. ISO 17123-7:2005 can be thought of as one of the first steps in the process of evaluating the uncertainty of a measurement (more specifically a measurand). The uncertainty of a result of a measurement is dependent on a number of factors. These include among others: repeatability, reproducibility (between-day repeatability) and a thorough assessment of all possible error sources, as prescribed by the ISO Guide to the expression of uncertainty in measurement (GUM). These field procedures have been developed specifically for in situ applications without the need for special ancillary equipment and are purposefully designed to minimize atmospheric influences and effects of imperfect adjustment of the optical plumbing instrument.