Why Is the Lower Hull Painted Red?为什么船底要漆成红色？

When large ships carry a lot of cargo， they sit quite low in the water. However， if a ship is empty， you’ll likely be able to see its lower hull， which will probably be painted red. There are several reasons why special paint of this color is used for marine vessels.

当大型船只乘载许多货物时，它们在水中会吃水相当深。然而，如果船只是空的，你可能会看到船身的下半部，它大概会被漆成红色。有几个原因可以解释为什么海洋船只要使用这种颜色的特殊涂料。

First and foremost， the red paint shields the underside of the ship. If left unprotected， the hull will eventually become covered with marine organisms such as barnacles， algae and mollusks， which will cause damage to the metal in the long run. Red marine paint gets its red color from copper oxide. This material acts as a biocide， a chemical compound that repels and prevents the growth of organisms. In addition， the paint guards the metal of the hull against corrosion from salt water， which can greatly weaken the structure and cause leaks.

首先，红色涂料保护着船的底部。如果不受保护，船底最终将会被像是藤壶、藻类和软体动物等海洋生物所覆盖，长此以往会对金属造成损坏。红色海洋涂料中的红色来自氧化铜。这种原料起着生物灭杀剂的作用——一种驱赶并防止生物生长的化学化合物。此外，该涂料能保护船底的金属免受盐水的腐蚀，这种腐蚀可能会大大地使结构松动并导致漏水。

Another reason for the red color is to indicate a vessel’s load status. The more the red paint is visible above the waterline， the lighter the load is. Having the hull painted red can also be helpful in case of an emergency by increasing a ship’s visibility. If a ship has capsized or is sinking， the red color of the hull contrasts with the blue or green color of the water. This gives other ships or rescue aircrafts a better chance of locating it.

使用红色的另一个原因是要显示船只的载荷状态。在吃水线以上可见的红色涂料越多，表示该船的负载越轻。将船底漆成红色在紧急情况下也很有帮助，可以增加船只的能见度。如果一艘船倾覆或正在下沉，船底的红色会与蓝色或绿色的海水形成对比，这提高了其他船只或救援飞机找到它的机会。

An underlying historical tradition further contributes to the preference for the color red. With its origins dating back over 2，000 years and popularity to this day， we are likely to continue seeing hulls painted red for a long time to come.

一个潜在的历史传统进一步促成了对红色的偏好。对红色的偏好，起源于两千多年以前，且至今仍相当流行，在未来很长一段时间内，我们很可能会继续看到漆成红色的船底。

Word Bank

hull /hʌl/ n. 船身；船体

repel /rɪ'pel/ v. 推开；赶走；驱除

The fabric has been treated to repel water.