Standard ultrahigh vacuum and flash filament techniques were used to measure the sticking probabilities of atomic and molecular hydrogen sH and sm, respectively, on graphite. Atomic hydrogen was produced by a hot tungsten filament. Graphite samples were specially fabricated ribbons which could be flashed to 2500 °K. The quantity of atomic hydrogen sorbed was found to be only dependent on the temperature of the graphite and the total number of incident hydrogen atoms. Thus it is possible to use a graphite ribbon as an atomic hydrogen detector.