Additional resources provided by the author
The mucous lining of the mouth cavity and nasal passages stores alcohol for some time after a person consumes alcohol. Normal body processes eliminate residual mouth alcohol within 15 minutes. Therefore, observe a subject for at least 15 minutes before performing a test. During the observation time, the subject may not eat, drink, or introduce any substance into his mouth. Furthermore, if the subject regurgitates, note the time and delay starting a breath test for at least 15 minutes.
[CMI, Inc., Basic Maintenance and Repair of the Intoxilyzer Breath Analysis Instrument, 10/1/84, p. 44.]