scope:

The stiffness of tooth-brushes, determined in accordance with a compromise method based on the BSI method and the French/Norwegian methods, was originally classified into five categories. However as a result of collaborative testing between laboratories it was subsequently decided to reduce the number of categories to three. This International Standard specifies a method for determining the stiffness of the tufted area of tooth-brushes and a means of assigning the stiffness so measured into categories of stiffness, i.e. - soft; - medium; - hard. This International Standard specifies a test method and grading scheme for the stiffness of the tufted area of conventional manual tooth-brushes, together with relevant information concerning definitions and information concerning testing machines.