Short answer: two numbers, not one. New York City deletes ASME A17.1 Section 2.29.1 and writes its own, and the replacement requires a building identification at a minimum of 2 inches and a separate New York City identification number at a minimum of a quarter inch. The controller carries both. So does the driving machine, the main line disconnect switch and the crosshead.
Appendix K is the city's modified version of ASME A17.1-2013. Because Section 2.29.1 is deleted and rewritten rather than amended, the whole requirement below is New York City's own text. More on how that works in what elevator code edition NYC actually uses.
Number one: the building identification
Appendix K, Section 2.29.1.1, in full:
"2.29.1.1 Each elevator shall be assigned a unique alpha-numeric or numerical identification, a minimum of 50 mm (2 in.) in height. The identification number shall be applied to the following locations:
(a) The driving machine;
(b) MG and/or Transformers set;
(c) Controller;
(d) Selector;
(e) Governor;
(f) Main line disconnect switch;
(g) The crosshead, or where there is no crosshead, the car frame, such that it is visible from the top of the car;
(h) The car operating panel, minimum of 13 mm (0.5 in.) in height;
(i) Adjacent to or on every elevator entrance at the designated level, minimum of 75 mm (3 in.) height; and
(j) Each bank of elevators shall be identified by an alphabetic letter."
Read the heights. The section sets 2 inches as the default, then overrides it twice. The car operating panel drops to half an inch. The designated landing goes up to 3 inches. A shop that prints one height for the whole job gets two of the ten wrong.
Item (g) is the one people forget, because it is the only placement specified by what an inspector can see rather than by what the part is called: on the crosshead, or on the car frame if there is no crosshead, "such that it is visible from the top of the car".
The section also closes the loop on how the number is built:
"Where an alpha-numeric designation is used for an elevator, the alpha portion shall represent the bank designation in which the elevator is located."
Number two: the New York City identification number
This is a different number, in a different size, in fewer places. Section 2.29.1.2:
"2.29.1.2 New York City Identification Number. Each elevator shall be assigned a unique numerical identification, a minimum of 6 mm (1/4 in.) in height. The City identification number shall be applied to the following locations:
(a) The driving machine;
(b) MG and/or Transformers set;
(c) Controller;
(d) Main line disconnect switch;
(e) The crosshead, or where there is no crosshead, the car frame, such that it is visible from the top of the car;
(f) The car operating panel (main panel only)."
Note what is missing from this second list against the first: no selector, no governor, no entrance at the designated level, no bank letter. And note that this one is numerical only, where the building identification may be alpha-numeric.
Five pieces of equipment therefore carry both numbers: driving machine, MG or transformer set, controller, main line disconnect switch, and the crosshead or car frame. That is where the two-tag habit comes from, and it is why a single combined tag is not always what the section asks for.
Shared machine rooms: everything gets labelled
Where one enclosure holds devices for more than one elevator, Section 2.29.1.3 requires each device, or a demarcated group of devices, to carry the identification assigned in 2.29.1.1. The section then lists nine of them, including:
"(f) "CAR DOOR BYPASS" and "HOISTWAY DOOR BYPASS" switches as required by Section 2.26.1.5"
and
"(d) stop switches as required by Section 2.7.6.5.2"
The rest of the list covers the governor trip and reset means, display devices, the means to move the car from outside the hoistway, landing inspection transfer switches, the manual resets for ascending car overspeed and unintended motion, and the earthquake reset. In a four-car machine room that is a lot of small labels, and 2.29.1.3 gives you the alternative in the same sentence: demarcate the group instead, so long as the demarcation establishes that everything inside it belongs to that elevator.
Escalators are separate again
Appendix K adds new Sections 6.1.9 and 6.1.10 for escalators. Section 6.1.9 is headed "New York City identification number" and reads:
"Each escalator shall be assigned a unique numerical identification a minimum of 6 mm (0.25 in) in height. The city identification number shall be applied on the right hand side, facing the newel, at the top and bottom of the escalator as well as the following locations:
(a) The driving machine;
(b) Controller;
(c) Main line disconnect switch."
And the building number:
"6.1.10 Building identification number. Each escalator shall be assigned a unique alpha-numeric or numerical identification, a minimum of 6 mm (0.25 in) in height. The building identification number shall be applied on the exterior, clearly visible, at the top or bottom of the escalator."
Both escalator numbers are a quarter inch. The 2 inch minimum is an elevator rule.
What to order
The NYC elevator ID tag ships blank so the device and city numbers can be stamped or engraved per car. If you are tagging a bank, count placements rather than cars: five items take both numbers, and a shared machine room adds the 2.29.1.3 list on top.
Send us the car list and the bank letters on WhatsApp and we will come back with a count and a price before you order.
Where this article stops
Everything above is quoted from New York City's own Appendix K text. We have not paraphrased the underlying ASME A17.1-2013 standard, which is copyrighted and not something we hold. Related reading: every sign NYC names around an elevator machine room and what NYC adds to a capacity and data plate.