What is the minimum horizontal tread depth for stairs in a public swimming pool?

The minimum horizontal tread depth for stairs in a public swimming pool is established to ensure safety and accessibility for users. A tread depth of 10 inches provides a sufficient surface area for individuals to place their feet securely when ascending or descending the steps. This dimension helps prevent slips and falls, which can be particularly hazardous in a wet environment like a swimming pool.

Standards for stair design, particularly in public areas, often require such dimensions to accommodate a range of users, including children, adults, and individuals with disabilities. By ensuring that the treads are adequately sized, pool facilities can enhance user safety and comply with relevant building codes and regulations.

The other sizes listed would either provide too little surface area, which could increase the risk of accidents, or exceed typical requirements, making them less practical for standard design standards. Thus, a tread depth of 10 inches strikes the right balance between safety, usability, and code compliance.