IEC 61094的本部分 -针对IEC 61094-1中规定的实验室标准话筒的自由场和压力灵敏度水平之间的差异，给出了一个多项式函数，该函数由多个实验室数据的最小二乘拟合得出， -通过将这些差异的值添加到压力灵敏度水平，可以确定空气中零度入射时实验室标准麦克风的自由场灵敏度水平， -给出频率和温度范围内多项式函数的列表值， -在没有合适的自由场校准时适用。

This part of IEC 61094 - gives a polynomial function derived from a least square fit to data from several laboratories, for the differences between free field and pressure sensitivity levels of laboratory standard microphones as specified in IEC 61094-1, - enables determination of the free field sensitivity level of a laboratory standard microphone for zero degrees incidence in air by adding values of these differences to the pressure sensitivity level, - gives tabulated values for the polynomial function for a range of frequency and temperature, - is applicable when a suitable free field calibration is not available.