Nina investigates how glass is made so strong. Engineers Aisha, Mollie and Suli visit Nina in her workshop and discover that glass can be made stronger if you put it in layers. Then they go to the Spinnaker Tower in Portsmouth to see Europe's largest glass floor.

Originally released by BBC Worldwide Learning, 2013. Streaming video file encoded with permission for digital streaming by Infobase on April 29, 2015.