Japan’s bridges aren’t exactly falling down, but industry officials fear that many might be on the verge of severe deterioration. Cement manufacturers say the standard guarantee for concrete durability is 50 years.  It means that a large number of concrete bridges, buildings and other structures erected during the nation’s high economic growth era will reach the end of the guarantee period in the coming years 
 
Taiheiyo Cement Corp and Oki Electric Industry Co. plan to market a new diagnostic system using integrated circuit tags as early as fiscal 2006. The radio tags, equipped with sensors to detect salt, carbon dioxide and other harmful substances, would be embedded in concrete structures 
 
Engineering consultant Nippon Koei Co. is considering marketing a basic diagnostic kit, including a small radar device, a salt measuring unit and other instruments. The company expects an increase in demand, particularly for inspection of condominiums and other buildings. The Japan Concrete Institute, meanwhile, has been holding a certification test for concrete inspection specialists since fiscal 2001.