TAPPI T 460 is a standard method for the measurement of paper air resistance, which is tested using the Gurley method. The method evaluates the vapor transmission rate of a certain volume of air by measuring the time it takes for it to pass through the paper at a specific pressure difference (1.22 kPa). The test range is usually 5 to 1800 seconds per 100 ml of air to pass through. This method is suitable for evaluating the characteristics of paper such as vapor transmission rate, fluid permeability, absorbency, apparent density (pb), and filtrate efficiency. Air resistance is affected by the internal structure of the paper and surface preparation, so it can be used for quality control in the production process.