Mine signaling quick reference is a paper note in Fallout 76.
Location[]
The note can be found sitting in an open locker in the weight room on the first floor of the Charleston Fire Department.
Transcript[]
While inside a mine or traveling as a group, talking needs to be kept to an absolute minimum. In order to communicate with others, your signal lamp should be used to communicate the following:
1 long flash, 1 quick flash - Proceed forward
2 long flashes - Halt in place
1 long flash, 1 quick flash, 1 long flash - Retreat immediately
Repeating flashes - Danger
For any of you who've previously worked in mines, this may be different than what you're used to. We were forced to change our signalling when folks started running into ambushes by some of the less hospitable survivors. If you see the old signaling, be aware it's probably not coming from a friendly source.