What are the standard pool fence regulations in the US?

Most US jurisdictions follow the International Swimming Pool and Spa Code (ISPSC) or similar guidelines. The basics: fence at least four feet tall, gaps no bigger than four inches, no horizontal rails or climbable features on the outside, and gates must self-close and self-latch with the latch out of a child’s reach (usually 54 inches from ground or on the pool side). Some places also require a secondary barrier like a pool cover or door alarm.