本实施规程规定了一种U型音频测试胶片，用于调整35mm电影磁音频复制机的机械和电气参数，该磁音频复制机用于条纹发行印刷品穿孔CS，以每秒24帧（96个穿孔）的速度（约90英尺[27米]每分钟[18英寸或457毫米每秒]）运行，以便进行适当的播放。国际标准化组织认可测试胶片的两个参考水平:参考水平为185 nWb/m的U型和参考水平为320 nWb/m的E型，以说明美国和欧洲常用的不同仪表类型。

This practice specifies a type U audio frequency test film to be used for adjusting the mechanical and electrical parameters of 35-mm motion-picture magnetic audio reproducers intended for striped release prints perforated CS, operating at 24 frames (96 perforations) per second (approximately 90 ft [27 m] per minute [18 in or 457 mm per second]) for proper playback.The International Organization for Standardization recognizes two reference levels for test films: Type U with a reference level of 185 nWb/m and type E with a reference level of 320 nWb/m, in order to account for differing meter types in common use in the United States and Europe.