What Do the Tiny Signs on NYC Subway Stairs Mean? - Untapped New York
Briefly

"The white signs are identifying labels that appear on a step riser, usually close to the middle or top of the staircase. The short code on each label reveals the staircase's location."
"An 'M,' 'S,' or 'P' are always the first letters to appear in the code. 'M' stands for mezzanine, 'S' stands for street, and 'P' stands for platform."
"The number in the middle of the code identifies which specific staircase you're on within the station. Since the stairs in the photo below are labeled with a '7,' we know there are at least seven staircases in that station."
"MTA workers use these labels internally for wayfinding and reporting. For example, they may note that 'M7B' needs to be repaired."
Read at Untapped New York
[
|
]