Abstract: When a pressure of a breath is kept to fall within a valid range, a CPU of a breath alcohol measuring apparatus updates a breath amount accumulation value that is an accumulation value of the amount of the breath blown into a mouth piece; when the breath pressure reaches the range outside the valid range, the CPU resets the breath amount accumulation value; and when the breath amount accumulation value reaches a valid breath amount, the CPU measures the alcohol concentration by an alcohol sensor. A breath pressure display portion is arranged at the position that can visually be recognized by a to-be-measured person who is blowing into the mouth piece.

Abstract: When a pressure of a breath is kept to fall within a valid range, a CPU of a breath alcohol measuring apparatus updates a breath amount accumulation value that is an accumulation value of the amount of the breath blown into a mouth piece; when the breath pressure reaches the range outside the valid range, the CPU resets the breath amount accumulation value; and when the breath amount accumulation value reaches a valid breath amount, the CPU measures the alcohol concentration by an alcohol sensor. A breath pressure display portion is arranged at the position that can visually be recognized by a to-be-measured person who is blowing into the mouth piece.

Abstract: A to-be-called side device includes an alcohol drinking state check means for performing an alcohol drinking state check of a user, a peripheral state obtaining means for obtaining peripheral states by sound and image to keep an illegal communication as to the check performed between a person who monitors the check and the user as evidence, a temporary record continuation means for continuing the temporary record of the peripheral states obtained by the peripheral state obtaining means, and a pre-check/post-check record means for recording the peripheral state for 10 minutes before the check and the peripheral state for 10 minutes after the check in the respective checks, wherein the pre-check/post-check record means obtains the record of the peripheral state at least before the check from the record by the temporarily record continuation means in the record of the peripheral states for 20 minutes before and after the check.