Precast concrete manufacturers use accelerated curing methods (steam) to achieve high early age strengths in prestressed concrete members to facilitate manufacturing and design requirements. A high early age strength is often required to enable efficient and cost-effective manufacture, mainly to allow early age transfer of stresses into a concrete girder. Australian Road Authority specifications often detail the way steam curing is to be applied on such elements. This is done specifically in terms of the delay period prior to the commencement of steam application, the rate of temperature rise in the chamber, the time for which a maximum temperature is maintained in the chamber, and how the chamber is allowed to cool. Specific requirements are also set down for maximum concrete temperatures in the girder elements and concrete strengths needed for stress transfer.