Local authorities and cities are expanding clean air zones and congestion charges in the fight to protect our city air, but these changes will take time. Does science offer a speedier solution?

Professor Anthony J Ryan OBE, Director of The Grantham Centre for Sustainable Futures & Professor of Physical Chemistry at The University of Sheffield and James Pack , of Sentinel RPI, An Energy, Carbon & Sustainability Consultancy for the Built Environment & PureTi join Mike Conway, Director at Camargue, to explore possible solutions to the question of cleaning our city air.