Never lose sight of the group. Especially if it goes back, we must never lose sight of the person immediately before us to prevent loss. This applies both to those who can stay behind and on the tail guide or “second” (the latter, which brings up the rear), and those who want to advance the guide head or “first” (which leads the way usually with more experience or knowledge of that particular trip), which can not be done.
These measures should be taken one to the letter if it is in poor visibility in fog or bad weather visibility conditions worsen, or if it is uniquely (for negligence or need) walking at night or in low light , natural or artificial.
