What characteristic defines a service saddle during installation?

A service saddle is designed to ensure that the load or pressure applied during its installation is distributed evenly around the pipeline. This characteristic is vital because it helps prevent stress points that could lead to leaks or pipe failure. When a service saddle is installed, it wraps around the pipe and securely holds a fitting or valve, thus providing support while minimizing the risk of damage.

In contrast, the other options do not correctly capture the essence of a service saddle's function. For instance, while it is true that service saddles can be used on both plastic and metal pipes, stating it is exclusively for plastic pipes is inaccurate. Additionally, service saddles are often used proactively to create new service connections rather than only for damaged pipes. Finally, they do not require welding; they typically rely on mechanical methods for installation, such as bolts or straps, making option A the most accurate choice.