Examkin

Question

Difficulty: Very hardBlood Alcohol Concentration (BAC) Limits and Thresholds

During a roadside traffic safety check, three individuals are tested for Blood Alcohol Concentration (BAC): Driver X is a 24-year-old operating a personal hatchback; Driver Y is a 20-year-old operating a personal sedan; and Driver Z is a 40-year-old Commercial Driver's License (CDL) holder operating their personal pickup truck for non-commercial errands. Chemical testing records a BAC of 0.05%0.05\% for all three drivers. Under standard statutory BAC threshold laws, which driver(s) are operating at or exceeding their legally mandated BAC limit?

  1. Only Driver YAnswer
  2. B
    Only Driver Y and Driver Z
  3. C
    Only Driver X and Driver Z
  4. D
    All three drivers (Driver X, Driver Y, and Driver Z)

Answer

Only Driver Y is operating at or exceeding the statutory Blood Alcohol Concentration (BAC) limit.
The option identifying 'Only Driver Y' is correct because statutory Zero Tolerance provisions set the legal BAC limit for drivers under 21 at 0.01%0.01\% to 0.02%0.02\%, making Driver Y's 0.05%0.05\% BAC a statutory violation. Drivers X and Z were operating personal vehicles, where the standard statutory adult BAC limit of 0.08%0.08\% applies.

Step-by-Step Solution

1
Evaluate the statutory BAC limit for Driver X (24-year-old adult driving a personal non-commercial vehicle)
The statutory per se BAC limit for non-commercial adult drivers aged 21 and older is 0.08%0.08\%. Driver X's BAC of 0.05%0.05\% is below this threshold.
Standard adult non-commercial vehicle operators are legally impaired per se at 0.08%0.08\% BAC or higher.
2
Evaluate the statutory BAC limit for Driver Y (20-year-old driver)
Under statutory Zero Tolerance laws for drivers under 21 years of age, the legal BAC threshold is 0.01%0.01\% to 0.02%0.02\%. Driver Y's BAC of 0.05%0.05\% significantly exceeds this limit.
Drivers under the legal drinking age of 21 are prohibited from operating motor vehicles with any measurable alcohol level.
3
Evaluate the statutory BAC limit for Driver Z (40-year-old CDL holder operating a personal vehicle for personal use)
The statutory 0.04%0.04\% BAC limit for commercial drivers applies specifically while operating a Commercial Motor Vehicle (CMV). When operating a personal vehicle for non-commercial errands, standard adult limits (0.08%0.08\%) apply. Driver Z's BAC of 0.05%0.05\% is below 0.08%0.08\%.
The reduced 0.04%0.04\% threshold is vehicle-specific and enforced during commercial vehicle operation.
4
Synthesize the results to determine compliant and non-compliant drivers
Only Driver Y has exceeded the applicable statutory limit (0.05%>0.01%–0.02%0.05\% > 0.01\%\text{--}0.02\%).
Driver X and Driver Z remain below their statutory threshold of 0.08%0.08\%.

Key Concept

Statutory BAC limits vary strictly based on driver age and vehicle classification: 0.08%0.08\% for adult non-commercial drivers, 0.04%0.04\% for commercial motor vehicle operation, and 0.01%–0.02%0.01\%\text{--}0.02\% under Zero Tolerance laws for drivers under 21.
Rate this question

Topics

Blood Alcohol Concentration (BAC) Limits and Thresholds

More questions from this topic