【多选题】
A have a luminous intensity of not less than 0.75 cd in all directions of the upper hemisphere.
B have a source of energy capable of providing a luminous intensity of 0.75 cd for a period of at least 6 h.
C be visible over as great a segment of the upper hemisphere as is practicable when attached to a lifejacket.
D be of white colour.
查看更多