Allan J R, Brennan D H, Richardson G
Environmental Sciences Division, RAF Institute of Aviation Medicine, Farnborough, Hants, U.K.
Aviat Space Environ Med. 1989 Mar;60(3):199-204.
The time to detect each of three underwater lights by six subjects was measured in clear and turbid (attenuation coefficient = 4.2.m-1) water, at distances of 1.54 m and 3.1 m, from two viewing angles, straight ahead (0 degrees) or 65 degrees to one side, and under three levels of ambient illumination. The lights were viewed either through a window, to simulate the use of a face mask, or with the subjects immersed. All lights were detected rapidly (less than 1 s) when viewed through the window in clear water. In turbid conditions, none of the lights was seen at 3.1 m by any subject. At a 1.54 m viewing distance, reliable detection by immersed subjects was found only in the clear water under the two darker ambient illuminations. In turbid water, detection was unreliable. We conclude that the design of underwater escape lighting should not rely on visibility over distances greater than 1.5 m, and that an illuminated guide-bar might provide valuable assistance in directing escape from aircraft.
在清澈和浑浊（衰减系数 = 4.2.m-1）的水中，让6名受试者在1.54米和3.1米的距离处，从两个视角（正前方（0度）或向一侧65度），并在三种环境光照水平下，测量检测三盏水下灯中每一盏灯的时间。这些灯要么通过窗户观看，以模拟使用面罩的情况，要么让受试者浸入水中观看。当在清澈的水中通过窗户观看时，所有的灯都能被迅速检测到（不到1秒）。在浑浊的条件下，没有任何受试者能在3.1米处看到任何一盏灯。在1.54米的观看距离下，只有在较暗的两种环境光照下的清澈水中，浸入水中的受试者才能可靠地检测到。在浑浊的水中，检测不可靠。我们得出结论，水下逃生照明的设计不应依赖于超过1.5米距离的能见度，并且一个有照明的导向杆可能在引导从飞机逃生方面提供有价值的帮助。
