Is the S4-5a sign is still used?
The S4-5a, Reduced School Speed Limit Ahead Sign text only sign is not allowed in New York State. The embedded speed limit sign version (S4-5) is the sign that shall be used. In addition, the color shall be the newer fluorescent yellow-green.
Here is the text from the NYS Supplement.
Section 7B.16 Reduced School Speed Limit Ahead Sign (S4-5, S4-5a)
INSERT the following paragraph:
The S4-5a sign shall not be used in New York.
Also, the text only advanced speed limit sign (W3-5a) is also not allowed. The embedded speed limit sign version (W3-5) is the sign that shall be used.
MUTCD info update - Cornell Local Roads Program