TEXAS VEHICLE EMISSIONS
INSPECTOR LICENSE EXAMINATION
PRACTICE QUESTIONS WITH
RATIONALES
Questions 150: Program Overview & Air Quality
1. What is the primary authority of the Texas Department of Public Safety
(DPS) regarding the vehicle emissions inspection program?
A) Setting federal air quality standards for the Clean Air Act
B) Certifying vehicle emissions inspection stations and inspectors ✓
C) Establishing maximum contaminant levels for drinking water
D) Enforcing commercial vehicle weight limits
Rationale: DPS is the primary state agency responsible for certifying
emissions inspection stations and inspectors in Texas, as outlined in 37 TAC
§23.55(a).
2. Motor vehicles are the largest source of which pollutants in Texas?
A) Carbon Dioxide (CO2) and Methane (CH4)
B) Hydrocarbons (HC) and Carbon Monoxide (CO) ✓
C) Sulfur Dioxide (SO2) and Particulate Matter (PM)
,D) Nitrogen Dioxide (NO2) and Ozone (O3)
Rationale: Motor vehicles are the largest source of hydrocarbon (HC) and
carbon monoxide (CO) emissions in Texas.
3. What is the primary contributor to ground level ozone (smog) formation?
A) Carbon Monoxide (CO) emissions
B) Hydrocarbons (HC) reacting with oxides of nitrogen (NOx) ✓
C) Particulate Matter (PM) emissions
D) Sulfur Dioxide (SO2) emissions
Rationale: Ground level ozone (smog) is primarily formed when hydrocarbons
(HC) react with oxides of nitrogen (NOx).
4. Approximately how much air pollution does a "typical" motor vehicle emit
annually?
A) 1/4 ton
B) 1/2 ton ✓
C) 1 ton
D) 2 tons
Rationale: A typical motor vehicle emits about 1/2 ton of air pollution
annually.
5. What is the primary purpose of OBD II?
A) To improve vehicle fuel economy
, B) To ensure vehicles emit a minimum level of pollutants through their useful
life ✓
C) To monitor tire pressure
D) To track vehicle mileage for maintenance
Rationale: The primary purpose of OBD II is to ensure that vehicles emit the
minimum amount of pollutants throughout their useful life.
6. Which of the following is NOT an affected county in Texas for emissions
testing?
A) Harris
B) Dallas
C) Bexar ✓
D) Tarrant
Rationale: The 17 affected counties are Brazoria, Collin, Dallas, Denton, Ellis,
El Paso, Fort Bend, Galveston, Harris, Johnson, Kaufman, Montgomery, Parker,
Rockwall, Tarrant, Travis, and Williamson. Bexar is not included.
7. What defines an "affected county" in the Texas emissions program?
A) A county with the highest population density
B) A county participating in an inspection and maintenance (I/M) program to
reduce harmful emissions from vehicles ✓
C) A county with the most vehicle registrations
D) A county designated by the EPA for air quality monitoring
, Rationale: An affected county is one participating in an inspection and
maintenance (I/M) program to reduce harmful emissions from vehicles.
8. What is a "designated vehicle" for emissions testing in Texas?
A) Any vehicle registered in Texas
B) A vehicle capable of being powered by gasoline, 224 years old, registered
in and primarily operated in an affected county ✓
C) Any vehicle over 25 years old
D) Only commercial vehicles
Rationale: A designated vehicle is capable of being powered by gasoline, is
224 years old, required to be registered in an affected county, and primarily
operated in an affected county.
9. Which vehicles are EXEMPT from emissions testing in Texas?
A) Gasoline powered vehicles 224 years old
B) Dieselpowered vehicles and motorcycles ✓
C) Vehicles registered in affected counties
D) All vehicles under 8,500 lbs GVWR
Rationale: No gasoline vehicles (including diesel vehicles) and motorcycles
are exempt from emissions testing.
10. What is the OBD II starting year for required testing?
A) 1994
B) 1995
INSPECTOR LICENSE EXAMINATION
PRACTICE QUESTIONS WITH
RATIONALES
Questions 150: Program Overview & Air Quality
1. What is the primary authority of the Texas Department of Public Safety
(DPS) regarding the vehicle emissions inspection program?
A) Setting federal air quality standards for the Clean Air Act
B) Certifying vehicle emissions inspection stations and inspectors ✓
C) Establishing maximum contaminant levels for drinking water
D) Enforcing commercial vehicle weight limits
Rationale: DPS is the primary state agency responsible for certifying
emissions inspection stations and inspectors in Texas, as outlined in 37 TAC
§23.55(a).
2. Motor vehicles are the largest source of which pollutants in Texas?
A) Carbon Dioxide (CO2) and Methane (CH4)
B) Hydrocarbons (HC) and Carbon Monoxide (CO) ✓
C) Sulfur Dioxide (SO2) and Particulate Matter (PM)
,D) Nitrogen Dioxide (NO2) and Ozone (O3)
Rationale: Motor vehicles are the largest source of hydrocarbon (HC) and
carbon monoxide (CO) emissions in Texas.
3. What is the primary contributor to ground level ozone (smog) formation?
A) Carbon Monoxide (CO) emissions
B) Hydrocarbons (HC) reacting with oxides of nitrogen (NOx) ✓
C) Particulate Matter (PM) emissions
D) Sulfur Dioxide (SO2) emissions
Rationale: Ground level ozone (smog) is primarily formed when hydrocarbons
(HC) react with oxides of nitrogen (NOx).
4. Approximately how much air pollution does a "typical" motor vehicle emit
annually?
A) 1/4 ton
B) 1/2 ton ✓
C) 1 ton
D) 2 tons
Rationale: A typical motor vehicle emits about 1/2 ton of air pollution
annually.
5. What is the primary purpose of OBD II?
A) To improve vehicle fuel economy
, B) To ensure vehicles emit a minimum level of pollutants through their useful
life ✓
C) To monitor tire pressure
D) To track vehicle mileage for maintenance
Rationale: The primary purpose of OBD II is to ensure that vehicles emit the
minimum amount of pollutants throughout their useful life.
6. Which of the following is NOT an affected county in Texas for emissions
testing?
A) Harris
B) Dallas
C) Bexar ✓
D) Tarrant
Rationale: The 17 affected counties are Brazoria, Collin, Dallas, Denton, Ellis,
El Paso, Fort Bend, Galveston, Harris, Johnson, Kaufman, Montgomery, Parker,
Rockwall, Tarrant, Travis, and Williamson. Bexar is not included.
7. What defines an "affected county" in the Texas emissions program?
A) A county with the highest population density
B) A county participating in an inspection and maintenance (I/M) program to
reduce harmful emissions from vehicles ✓
C) A county with the most vehicle registrations
D) A county designated by the EPA for air quality monitoring
, Rationale: An affected county is one participating in an inspection and
maintenance (I/M) program to reduce harmful emissions from vehicles.
8. What is a "designated vehicle" for emissions testing in Texas?
A) Any vehicle registered in Texas
B) A vehicle capable of being powered by gasoline, 224 years old, registered
in and primarily operated in an affected county ✓
C) Any vehicle over 25 years old
D) Only commercial vehicles
Rationale: A designated vehicle is capable of being powered by gasoline, is
224 years old, required to be registered in an affected county, and primarily
operated in an affected county.
9. Which vehicles are EXEMPT from emissions testing in Texas?
A) Gasoline powered vehicles 224 years old
B) Dieselpowered vehicles and motorcycles ✓
C) Vehicles registered in affected counties
D) All vehicles under 8,500 lbs GVWR
Rationale: No gasoline vehicles (including diesel vehicles) and motorcycles
are exempt from emissions testing.
10. What is the OBD II starting year for required testing?
A) 1994
B) 1995
