The Zorbonaut, the person enjoying the thrill of Zorbing, climbs into the inside ball through a hole or kind of tunnel that passes through the outside ball. There is more than 2 ft. of air between the Zorbonaut and theground to protect the person from the effects of the ball bouncing along. Now the Zorb has been fully tested to make sure it is completely safe, which wasn't what happened originally. "I broke my arm in the prototype, but we have done our best to prevent injury since then," says Andrew. Only the strongest materials have been used to make Zorbs. The plastic does not tear and the outside ball is designed so that it does not lose its shape. After designers had been experimenting for a long time, they made Zorbs with harnesses to keeppeople safely in position while they are zorbing on their own or with a friend.