Which metal parts of therapeutic tubs must be bonded together?

In therapeutic tubs, bonding refers to the practice of electrically connecting various metal parts to ensure safety by preventing electrical shock. The correct answer indicates that all metal parts, which include the motor components, the metal frame, and the electrical components, must be bonded together. This is crucial because any unbonded metal can pose a serious risk if it becomes energized due to a fault in the electrical system.

By bonding these components, you ensure that in the event of a fault, electrical current is redirected safely to the ground rather than allowing any part to become live, which could lead to electric shock. This practice is mandated by electrical codes and safety standards to protect users from electrical hazards. Thus, it is essential to bond all metal parts within therapeutic tubs to maintain a safe environment for users.