In the paper industry it is common practice to make so-called hand sheets of pulps to determine the physical and optical properties before going to production or from the production of pulp. One of the systems to produce these hand sheets is the Rapid-Köthen method. In this method a container, with on the bottom a screen, is filled with the pulp dilution. Then after homogenizing the pulp in the container, a valve on the bottom is opened and the water is drained leaving the pulp on the screen. The wet sheet is transferred from the screen to the dryer by means of the carrier board. A paper cover sheet is placed on top. In the dryer the sheet is dried between the carrier board and paper cover sheet. The carrier board and paper cover sheet are removed when the sheet is dry. After conditioning, the sheet is ready for testing.

Carrier boards are circular sheets of bleached lined folding boxboard, without colorants or fluorescent whitening agents, having a diameter of 240 mm, a grammage of 200 g/m², and a well-sized surface. The paper cover sheets are circular sheets of well-sized calendared paper, with a grammage of 65 g/m² and a diameter of 205 mm.

The carrier board and paper cover sheet are used with a hand sheet former for physical testing conform ISO 5269-2: Pulps – Preparation of laboratory sheets for physical testing – Part 2: Rapid-Köthen method.