Abstract: An apparatus for in vivo measurement of carbon monoxide production rate comprising a first gas detector for detecting the concentration of a first selected gas in at least first and second gas samples, the first gas detector being adapted to provide output signals corresponding to the first selected gas concentration in the first and second gas samples; a second gas detector adapted to substantially simultaneously detect the concentration of at least second and third selected gases in the first and second gas samples, the second gas detector being further adapted to provide output signals corresponding to the second and third selected gas concentrations in the first and second gas samples; means for providing the first and second gas samples to the first and second gas detectors; and processing means for determining the rate of carbon monoxide production in at least the second sample in response to the first and second gas detectors output signals.

Abstract: An acoustic coupling device for a hearing screening device comprising engagement means being adapted to receive an acoustic stimulus from the hearing screening device and transmit at least one response signal from a subject (or patient) to the hearing screening device, stimulus monitoring means in communication with the engagement means for monitoring the acoustic stimulus, at least a first earpiece disposed proximate the cavity of at least one of said subject's ears having a stimulus input in communication with the engagement means adapted to receive the acoustic stimulus, the stimulus input being further adapted to receive and transmit the response signal from the subject to the engagement means, the earpiece further including a response signal output adapted to receive and transmit the response signal, and response signal monitoring means in communication with the response signal output for monitoring the response signal.

Abstract: An acoustic coupling device for a hearing screening device comprising a coupling input adapted to removeably engage a hearing screening device, the coupling input being adapted to receive an acoustic stimulus from the hearing screening device and transmit at least one response signal from a subject (or patient) to the hearing screening device; a first passive attenuator adapted to attenuate a first frequency of the acoustic stimulus; a second passive attenuator adapted to attenuate a second frequency of the acoustic stimulus, the first and second passive attenuators in combination providing a second acoustic stimulus having a substantially balanced acoustic spectrum; at least a first earpiece disposed proximate the ear canal of one of the subject's ears, the earpiece including a stimulus input adapted to transmit at least the second acoustic stimulus to the subject and receive at least a first response signal having a first volume from the subject's ear; and a response signal compensator adapted to