Before water entry, where should the RS's mask be tied off on the harness?

The mask should be tied off on the left or right shoulder strap of the harness to ensure it remains secure and easily accessible before water entry. This positioning allows the rescue swimmer to quickly reach for the mask when needed, without the risk of it becoming entangled or lost in the water. By securing it to the shoulder strap, it is kept in a location that minimizes interference with movement and maintains a streamlined profile, essential for effective water entry and swimming.

Additionally, tying off the mask in this manner ensures that it's positioned in a way that allows for rapid deployment once the swimmer enters the water. This is particularly important in rescue scenarios where time and efficiency can significantly impact the outcome of the operation. It also enhances the overall safety and readiness of the rescue swimmer, as they can focus on the rescue without fumbling for equipment.