Abstract: Herein disclosed is an exhalation inspecting apparatus for use, for example, with a device mounted on an automotive vehicle for producing warning signals or disabling the vehicle from being started from rest condition if the inspecting apparatus detects an alcohol concentration higher than an allowable limit in air exhaled by a subject or an intending driver. The inspecting apparatus is responsive not only to the alcohol concentration of the subject's exhaled air but to breakage of electric lines connected to detecting elements incorporated in the inspecting apparatus and causes the warning or locking device to be operative in case the electric lines happen to be broken.