New York Codes, Rules and Regulations
Title 1 - DEPARTMENT OF AGRICULTURE AND MARKETS
Chapter VI - Food Control
Subchapter E - Retail Food Stores (Article 19 Agriculture and Markets Law)
Part 271 - Retail Food Store Sanitation Regulations
Subpart 271-6 - Sanitary Facilities and Controls
Section 271-6.24 - Openings

Openings to the outside shall be effectively protected against the entry of rodents. Outside openings shall be protected against the entry of insects by tight-fitting, self-closing doors, closed windows, screening, controlled air currents, or other means. Screen doors shall be self-closing and screens for windows, skylights, transoms, intake and exhaust air ducts and other openings to the outside shall be tight-fitting and free of breaks. Screening material shall be not less than 16 mesh to the inch.