An image reader is composed of a read unit 2 provided with a contact member 21 which abuts an original bed 11 of a flat bed unit 1; and a pressing element 30 for causing the read unit 2 and the original bed 11 to press against each other. The traffic channel assignment is retained for use by the terminal while the terminal is idle between data traffic transmissions to the satellite in response to a type of service designation that is associated with the terminal. The method includes a step for treating andor making optical devices in the presence of a flame produced by the combustion of deuterium gas or a mixture including deuterium. The maximum likelihood ratio test can incorporate the output of each sensor relating to the occupant, and can further incorporate data sets related to the outputs of each of the sensors in response to a plurality of test cases, for a specific class of occupants.