1
Texas Vehicle Emissions Inspector Exam — 100 Original Practice Questions
Program Overview & Air Quality (1–15)
1. What is the primary purpose of the Texas Vehicle Emissions Inspection Program?
A) To generate revenue for the state
B) To reduce air pollution by identifying vehicles with excessive emissions
C) To inspect vehicle safety features only
D) To test vehicle performance
Answer: B. The program is designed to reduce air pollution by identifying vehicles that
exceed allowable emission standards and ensuring they are repaired before registration .
2. Which state agency administers the Texas Vehicle Emissions Inspection Program?
A) Texas Department of Transportation (TxDOT)
B) Texas Commission on Environmental Quality (TCEQ)
C) Texas Department of Public Safety (DPS)
D) Texas Department of Motor Vehicles (TxDMV)
Answer: C. The Texas DPS administers the Vehicle Emissions Inspection Program, including
licensing inspectors and inspection stations .
3. Motor vehicles are the largest source of which pollutant in Texas?
A) Carbon dioxide
B) Ground-level ozone (smog)
C) Sulfur dioxide
D) Lead
Answer: B. Motor vehicles are the largest source of ground-level ozone (or smog) in Texas .
4. A "typical" vehicle emits approximately how much air pollution annually?
A) 100 pounds
B) 500 pounds (half a ton)
C) 1,000 pounds (one ton)
D) 2,000 pounds (two tons)
Answer: B. A "typical" vehicle emits about a half-ton of air pollution annually .
5. Motor vehicle-related smog damages which body system?
A) Digestive system
B) Lung tissue
C) Skeletal system
D) Nervous system
Answer: B. Motor vehicle-related smog (ground-level ozone) damages lung tissue and
aggravates respiratory disease .
6. What is the primary purpose of OBD II?
A) To measure tire pressure
, 2
B) To ensure vehicles emit the minimum amount of pollutants through their useful life
C) To calculate fuel economy
D) To determine insurance rates
Answer: B. The primary purpose of OBD II is to ensure that vehicles emit the minimum
amount of pollutants through their useful life .
7. Which federal law requires states to implement emissions inspection programs in
nonattainment areas?
A) Clean Water Act
B) Clean Air Act
C) Safe Drinking Water Act
D) Resource Conservation and Recovery Act
Answer: B. The program is part of the state's effort to comply with federal Clean Air Act
requirements in nonattainment areas .
8. How many affected counties currently participate in the Texas emissions inspection
program?
A) 5
B) 10
C) 17
D) All 254
Answer: C. The DPS training manual identifies 17 counties participating in the emissions
testing program .
9. Which of the following is NOT an affected county for Texas emissions testing?
A) Harris County
B) Travis County
C) Bexar County (as of 2026)
D) Bexar County (before November 2026)
Answer: D. Bexar County becomes an emissions county beginning November 1, 2026 .
10. Which pollutant is NOT measured by the ASM2 test?
A) Hydrocarbons (HC)
B) Carbon monoxide (CO)
C) Nitrogen oxides (NOx)
D) Sulfur dioxide (SO2)
Answer: D. The ASM2 test measures hydrocarbon, carbon monoxide, and nitrogen oxides .
11. What is the primary contributor to ground-level ozone formation?
A) Carbon dioxide
B) Hydrocarbons reacting with oxides of nitrogen
C) Water vapor
D) Oxygen
, 3
Answer: B. Hydrocarbons (HC) reacting with oxides of nitrogen (NOx) are the primary
contributors to ground-level ozone .
12. A malfunctioning vehicle emits how much more pollution than a typical vehicle?
A) The same amount
B) Twice as much
C) Many times the amount
D) Half as much
Answer: C. A malfunctioning vehicle emits many times the amount of pollution of a "typical"
vehicle .
13. What does the Texas I/M program stand for?
A) Inspection and Maintenance
B) Inspection and Measurement
C) Internal and Mechanical
D) Inspection and Monitoring
Answer: A. I/M stands for Inspection and Maintenance .
14. Which agency certifies the emissions testing equipment used in Texas?
A) DPS
B) TCEQ
C) TxDOT
D) EPA
Answer: B. The Texas Commission on Environmental Quality (TCEQ) certifies emissions
testing equipment .
15. What is the environmental objective of the Texas emissions program?
A) Increase vehicle registration
B) Improve regional air quality and meet federal clean air standards
C) Reduce fuel costs
D) Promote electric vehicles
Answer: B. The program helps reduce pollutants while supporting compliance with federal
Clean Air Act requirements .
Vehicle Applicability & Exemptions (16–30)
16. What model year threshold requires OBD II systems in gasoline-powered vehicles?
A) 1990
B) 1996
C) 2000
D) 2005
Answer: B. OBD II systems were required on all model year 1996 or newer gasoline-powered
vehicles .
Texas Vehicle Emissions Inspector Exam — 100 Original Practice Questions
Program Overview & Air Quality (1–15)
1. What is the primary purpose of the Texas Vehicle Emissions Inspection Program?
A) To generate revenue for the state
B) To reduce air pollution by identifying vehicles with excessive emissions
C) To inspect vehicle safety features only
D) To test vehicle performance
Answer: B. The program is designed to reduce air pollution by identifying vehicles that
exceed allowable emission standards and ensuring they are repaired before registration .
2. Which state agency administers the Texas Vehicle Emissions Inspection Program?
A) Texas Department of Transportation (TxDOT)
B) Texas Commission on Environmental Quality (TCEQ)
C) Texas Department of Public Safety (DPS)
D) Texas Department of Motor Vehicles (TxDMV)
Answer: C. The Texas DPS administers the Vehicle Emissions Inspection Program, including
licensing inspectors and inspection stations .
3. Motor vehicles are the largest source of which pollutant in Texas?
A) Carbon dioxide
B) Ground-level ozone (smog)
C) Sulfur dioxide
D) Lead
Answer: B. Motor vehicles are the largest source of ground-level ozone (or smog) in Texas .
4. A "typical" vehicle emits approximately how much air pollution annually?
A) 100 pounds
B) 500 pounds (half a ton)
C) 1,000 pounds (one ton)
D) 2,000 pounds (two tons)
Answer: B. A "typical" vehicle emits about a half-ton of air pollution annually .
5. Motor vehicle-related smog damages which body system?
A) Digestive system
B) Lung tissue
C) Skeletal system
D) Nervous system
Answer: B. Motor vehicle-related smog (ground-level ozone) damages lung tissue and
aggravates respiratory disease .
6. What is the primary purpose of OBD II?
A) To measure tire pressure
, 2
B) To ensure vehicles emit the minimum amount of pollutants through their useful life
C) To calculate fuel economy
D) To determine insurance rates
Answer: B. The primary purpose of OBD II is to ensure that vehicles emit the minimum
amount of pollutants through their useful life .
7. Which federal law requires states to implement emissions inspection programs in
nonattainment areas?
A) Clean Water Act
B) Clean Air Act
C) Safe Drinking Water Act
D) Resource Conservation and Recovery Act
Answer: B. The program is part of the state's effort to comply with federal Clean Air Act
requirements in nonattainment areas .
8. How many affected counties currently participate in the Texas emissions inspection
program?
A) 5
B) 10
C) 17
D) All 254
Answer: C. The DPS training manual identifies 17 counties participating in the emissions
testing program .
9. Which of the following is NOT an affected county for Texas emissions testing?
A) Harris County
B) Travis County
C) Bexar County (as of 2026)
D) Bexar County (before November 2026)
Answer: D. Bexar County becomes an emissions county beginning November 1, 2026 .
10. Which pollutant is NOT measured by the ASM2 test?
A) Hydrocarbons (HC)
B) Carbon monoxide (CO)
C) Nitrogen oxides (NOx)
D) Sulfur dioxide (SO2)
Answer: D. The ASM2 test measures hydrocarbon, carbon monoxide, and nitrogen oxides .
11. What is the primary contributor to ground-level ozone formation?
A) Carbon dioxide
B) Hydrocarbons reacting with oxides of nitrogen
C) Water vapor
D) Oxygen
, 3
Answer: B. Hydrocarbons (HC) reacting with oxides of nitrogen (NOx) are the primary
contributors to ground-level ozone .
12. A malfunctioning vehicle emits how much more pollution than a typical vehicle?
A) The same amount
B) Twice as much
C) Many times the amount
D) Half as much
Answer: C. A malfunctioning vehicle emits many times the amount of pollution of a "typical"
vehicle .
13. What does the Texas I/M program stand for?
A) Inspection and Maintenance
B) Inspection and Measurement
C) Internal and Mechanical
D) Inspection and Monitoring
Answer: A. I/M stands for Inspection and Maintenance .
14. Which agency certifies the emissions testing equipment used in Texas?
A) DPS
B) TCEQ
C) TxDOT
D) EPA
Answer: B. The Texas Commission on Environmental Quality (TCEQ) certifies emissions
testing equipment .
15. What is the environmental objective of the Texas emissions program?
A) Increase vehicle registration
B) Improve regional air quality and meet federal clean air standards
C) Reduce fuel costs
D) Promote electric vehicles
Answer: B. The program helps reduce pollutants while supporting compliance with federal
Clean Air Act requirements .
Vehicle Applicability & Exemptions (16–30)
16. What model year threshold requires OBD II systems in gasoline-powered vehicles?
A) 1990
B) 1996
C) 2000
D) 2005
Answer: B. OBD II systems were required on all model year 1996 or newer gasoline-powered
vehicles .
