NEW APPARATUS FOR THE DETERMINATION OF BREATH ALCOHOL : "ALCOLINGER AUTOMATIC" D. MONNIER, L. ETZLINGER and F. MUSSANO + The drawback of the apparatus for the dosage of breath alcohol (such as the Breathalyzer and the Ethanographe) which, in other respects, are excellent instruments, is due to the rather high number of operations necessary. To palliate this drawback, we have built an automatic device which, thanks to a programmer, reduces the manipulations to a strict minimum and insures an almost complete security of the analytical operations. It is impossible, for instance, to omit one of the manipulations (the flushing, for ex.) and these follow one another according to an immutable cycle. Working principle This analysis apparatus is formed of a gaseous circuit through which circulates the breath. It comprises a mouthpiece connected by a rubber tube to a serpentine-worm of a rigorously determined volume into which the breath is collected, fitted with a system of controlled valves ; the other end of the worm is connected to a bubbler which plunges in an ampoule containing the reagent (a titrated solution of potassium dichromate, for instance). On the circuit are placed four valves which, by their alternated and synchronized action, insure successively the various operations. An impulsion system drives a cam programmer which controls the whole of the operations, viz. the complete flushing of the apparatus the time of which has been fixed so that every impurity is completely eliminated, in particular traces of alcohol from a previous analysis. A luminous signal indicates that the flushing is ended, the programmer opens the valve which connects the mouthpiece to the worm. The subject can then blow during a time fixed by the programmer and in such a way that the first blowing phase is eliminated, and that, once the operation is ended, the worm contains only alveolar air. After this period, the end of which is also indicated by a luminous signal, the inlet valve closes automatically. If the blowing is not sufficient or is interrupted, the apparatus stops and the whole analysis must be made again, including the flushing of the instrument. The "accelerator" button is then pushed and in a few seconds it brings the apparatus on the initial position "start". When the collection has been effected correctly, the programmer puts in motion a membrane pump and at the same time opens the inlet valve. The breath is then pushed into it. After the whole breath has passed through the ampoule, the time and speed of passage of the gas and vapours being set once for all, and in
such a way that the breath alcohol is quantitatively retained in the reagent, the programmer stops the membrane pump The reaction time is also programmed and the end is marked by the complete stoppage of the apparatus : extinction of the luminous signals. The operator turns off, by means of a button, the circuit of the microamperemeter and reads directly on the latter the level of blood in /oo ^Alcohol weight 0, Blood weight '' The apparatus is then ready for another analysis. It suffices to change.the ampoule. A series of luminous indexes of various colours permits to follow the cycle. The duration of the dosage is of about 3 minutes. The dosage is based on the variation, under the effect of the ethanol, of the coloration of the reagent contained in the ampoule. In the case of dichromate, the weakening of the yellow coloration of this reagent is measured by spectrophotometry with a standard ampoule. The determination of alcohol concentration is made by spectrophotomctric means. It is based on the reductible reaction of the latter on the potassium dichromate. The alcohol reduces the dichromate, and this provokes a weakening of the latter*s coloration, weakening which is measured in relation to a standard solution contained in an ampoule incorporated in the apparatus. It is not accessible. The device is constituted by a tungsten lamp placed between two photoelectric cells ; before each is a potassium dichromate ampoule and a filter giving monochromatic rays. One of the ampoules serves as a standard ; the other receives the alcoholized breath. After the flushing, the microamperemeter is put on zero by a setting screw. After the passage of the breath, there is a lack of balance of the photoelectric cells which is manifested by a current that is measured on a microamperemeter graduated directly in %o of blood alcohol (77;- D^ - ~ - /0o). The reading is Blood weight J made 30 seconds after the end of the passage of breath, time necessary for the reaction. Security of the dosage Everything has been done to avoid errors of handling. Thus, the analysis cannot be carried out if the complete flushing of the apparatus has not been effected previously. On the other hand, the cycle follows its course only if the collection has been correctly made. The liquid of the test ampoule cannot, whatever the errors of operation, be sucked up in the interior of the apparatus as is the case with certain analysis instruments. Only one error remains possible : to forget to put the apparatus on zero after the flushing.
Advantages of the proposed device Apart from the programmer, there is no movable part, therefore no wear, nor possibility of stoppage of the driving system. As the collection chamber is a spiral and is not fitted with a piston, the flushing and collection being made by simple sweeping, there is, also in this case, no possible stoppage. With piston cylinders, it rather frequently happens that the piston jams during an analysis owing to dust particles, which necessitates a dismantling of the apparatus. The instrument presents a great versatility. For instance, by modifying the programmer, one can change the time of various operations, thus allowing any other method of spectrophotometric dosage. On the other hand, the microamperemeter being fitted with a po t e n t i o m e t e r, it is possible, by means of a screw, to change its sensitivity, which may be useful to certain police officers who might wish that the results obtained with the apparatus be slightly lower than the value obtained by the blood analysis. Let us notice that thanks to luminous signals judiciously placed, the operator can follow the various cycle phases. This device is not indispensable : it has no influence on the result of the dosage. Feeding of the apparatus The apparatus works either by means of 12 volt batteries, or on the town*s alternating current. In the latter case, one disposes of a stabilizer reducer which gives continuous current and eliminates all variations of the inlet tension which are frequent and sometimes rather important. Directions for the use of the Ethanographe "Alcolinger Automatic" 1. Put the apparatus under tension (220 or 12 volts). Place an ampoule in its lodging and connect it by means of a bubbler to the collection system (red rubber). Wait until the thermometer reaches 45-50 C. 2. Push the "start" button and wait until the light "zero setting" is on. Bring the hand of the reading instrument on zero by pushing the "photometer" button and by turning the knob "luminous source". 3. Fix a mouthpiece to the "collection" tube. Let the subject blow without interruption until the "blow" light is on. 4. Wait until the "cycle" light is out. Press the "photometer" button and make the reading on the scale graduated in promille of blood alcohol (promille/weight). A few results We have effected in the Analytical Laboratories of the Geneva University a few comparative experiments to test the automatic apparatus described above. We had at our disposal an ordinary Ethanographe and two gas chromatograph apparatus,
one equipped for the dosage of gases and vapours, the other for the dosage of blood alcohol. Three persons : two men and a woman, have submitted to an experiment, the results of which are given below : Mr A 21 year-old 75 kgs Drink : 2:15 p.m. 150 cc cognac brandy 2:25 p.m. end of drinking T ime Alcolinger Ethanographe Gas Chromatograph p.m. Automatic Breath Blood 2:55 0,44 _ - - j 2:58 -. - - - 3:05 - - 0,46-3:15 0,54 - - - 3:25-0,55 - - 3:30 - - 0,59-3:45 0,52 - - - 3:52-0,48 - - 3:55 - - - 0,46 4:10 - - 0,44 - Mr B 23 year-old 76 kgs Drink 2:15 p.m. 150 cc cognac brandy 2:25 D.m. end of drinking 3:05 0,53 - - - 3:10-0,56 - - 3:15 - - 0,69-3:30 0,67 - - - 3:36-0,57 - - 3:40 - - 0,61-3:55 0,53 - - - 4:00-0,52 - - 4:15 - - - 0,52 4:20 - - 0,50-4 :22 0,49 - - - II. 30
Miss C 21 year-old 46 Kgs Drink : 4:30 p.m. 50 cc cognac brandy T ime Alcolinger Ethanographe Gas Chromatograph p.m. Automatic Breath Blood 5:00 0,47-5:05-0,47 - - 5:10 - - - 0,42 c 5:30 0,40 - - - 5:35-0,36 - - 6:05 0,28 - - - 6:06-0,30 - - c II. 31