We investigated the dependence of hydrogen sensing on the hydrogen density at 0.1-100 vol% in air atmosphere by commercially available diaphragm and quartz friction pressure gauges (D- and Q-gauges). It was demonstrated that the Q-gauge pressure reading depends on the hydrogen concentration for concentrations up to 100 vol% and can be used to measure the hydrogen concentration in air. The response times using the dual pressure gauges were shown to be below one second for hydrogen concentrations of 0.1-100 vol% in air atmosphere, indicating that our hydrogen-sensing method has a rapid response in the above range of hydrogen concentrations. In conclusion, hydrogen sensing with dual pressure gauges can be used to measure a wide range of hydrogen concentrations with a fast response; thus, this method is particularly practical for ensuring a safe hydrogen-based economy. (C) 2008 International Association for Hydrogen Energy. Published by Elsevier Ltd. All rights reserved.