A swimming pool enclosure must not be made out of which material?

A swimming pool enclosure must not be made out of chain link because it does not provide adequate security and safety for preventing unauthorized access to the pool area. Chain link fencing often has gaps that can allow small children or pets to slip through, making it less effective at containing individuals and ensuring a safe swimming environment.

In contrast, materials such as wood, plastic, and glass can provide a more solid barrier. Wood fencing can be built to be tall enough to deter entry, plastic fencing can be made solid and durable, and glass enclosures can be designed to create a clear yet secure barrier. Each of these materials can offer different levels of visibility and aesthetic appeal while also maintaining a secure environment around the pool.