The breath- and blood-alcohol specimens in this study were collected within one hour of each other. The mean blood alcohol concentration obtained was 0.180 gram/deciliter (g/dl), with a range from zero to 0.338 g/dl. By comparison, the mean Intoxilyzer 5000 result was 0.16 g/dl with a range from zero to 0.32 g/210 liter. Compared with the blood-alcohol result Intoxilyzer 5000 results were lower by more than 0.01 g/210 1 67 percent of the time, within 0.01 g/210 1 32 percent of the time, and higher by more than 0.01 g/210 1 2 percent of the time. 2 figures, 1 table, and 17 references. (Author abstract)