What dimension must the outer banks of a bowling green exceed in height?

The dimension for the outer banks of a bowling green is specified to exceed 230 mm in height. This standard is in place to ensure that the banks effectively contain the bowling green's surface and its playing area while contributing to the overall integrity of the game. A height of at least 230 mm provides adequate support and helps prevent the bowls from rolling off the green, thereby enhancing playability and maintaining a fair playing field. It also assists in managing weather-related issues, such as rainwater drainage, ensuring that the green remains in prime condition for play. The importance of having this minimum height standard is to preserve the sport's quality and standards.