N.Y. Multiple Residence Law § 132: Stairs

§ 132. Stairs. Every interior and exterior stair and fire-stair shall

be provided with proper balustrades and handrails. Every such stair and

fire-stair three feet eight inches or more in width shall be provided

with a handrail on each side. Each tread, exclusive of nosing, shall be

not less than nine and one-half inches wide; each riser shall not exceed

seven and three-quarter inches in height; and the product of the number

of inches in the width of the tread and the number of inches in the

height of the riser shall be at least seventy and at the most

seventy-five. Winding stairs shall be unlawful in any public part of the

dwelling.