N.Y. Comp. Codes R. & Regs. Tit. 12 §§ 146-2.9
On any day that a service employee or food service worker works at a non-tipped occupation:
Example:
An employee has a daily schedule as follows: 8 a.m. to 9:45 a.m., food preparation; 9:45 a.m. to 1:30 p.m., serving food in the restaurant; takes 1/2 hour meal period; 2:00 p.m. to 4:30 p.m. serving food in the restaurant. That employee has worked 8 hours total, consisting of 6 hours, 15 minutes as a food service worker and 1 hour, 45 minutes in a non-tipped occupation. Twenty percent of an 8 hour shift is 1 hour, 36 minutes. Although the employee worked for less than two hours at the non-tipped occupation, he/she has worked for more than 20 percent of his/her shift at the non-tipped occupation. Therefore, the employee is subject to no tip credit for that day.
N.Y. Comp. Codes R. & Regs. Tit. 12 §§ 146-2.9