Required installation under the international regulations for preventing collisions at sea. The frequency of the horns shall be between 130 – 350 Hz for a vessel greater than 75 mtrs but less than 200 mtrs in length, and 70 – 200 Hz for a vessel 200 mtrs or more in length.
根据国际海上避碰规则要求安装。对于长度大于75公吨但小于200公吨的船只,喇叭的频率应在130-350赫兹之间;对于长度为200公吨或以上的船只,喇叭的频率应在70-200赫兹之间。