At the request of Thermphos, CE has carried out a study to explore the definition of ‘waste’. Thermphos is a supplier of phosphoric acid which, after use, is sent back to the company. On return the spent acid is classified as a waste material, however. This study indicates that reusing this phosphoric acid is environmentally far preferable to treating it as waste and disposing of it accordingly (in controlled land-fill). For Thermphos, the spent acid is a satisfactory raw material and defining it as waste creates an unwarranted financial and administrative burden, as well as being bad for the company’s image.