本文对声强测量中声场抗性指数、有关判据以及不确定度限制规则作了详细的阐述。并且,选择了两组五种不同的初始测量条件,采用声强法对Jo41—4型三相异步电动机作了声功率级测定。结果表明:采用声强法进行测量时,只要按照不确定度限制规则及其判据进行,就能得到达到预期精度的测量结果。 In this paper, the acoustic field resistance index, the relevant criteria and the rules of the uncertainty limit are described in detail. And two sets of five different initial measurement conditions were selected, and the sound power level of Jo41-4 three-phase asynchronous motor was measured by sound intensity method. The results show that when using the sound intensity method to measure, as long as the rules and the criteria of the uncertainty limit are followed, the measurement result with the expected accuracy can be obtained.