1.1本试验方法包括使用引起宽度收缩的桥梁作为计量装置计算明渠或溪流中的水流量（体积流量）。 1.2本试验方法为一次水流事件（通常为特定洪水）产生最大流量。计算流量可用于帮助定义水位流量关系的高水位部分。 1.3以英寸-磅为单位的数值应视为标准值。括号中给出的国际单位仅供参考。 1.4本标准无意解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全和健康实践，并确定监管限制的适用性。

1.1 This test method covers the computation of discharge (the volume rate of flow) of water in open channels or streams using bridges that cause width contractions as metering devices. 1.2 This test method produces the maximum discharge for one flow event, usually a specific flood. The computed discharge may be used to help define the high-water portion of a stage-discharge relation. 1.3 The values stated in inch-pound units are to be regarded as the standard. The SI units given in parentheses are for information only. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.