Page 1 of 67
TEXAS VEHICLE EMISSIONS INSPECTOR
LICENSE EXAMINATION — 2026 CERTIFICATION
ASSESSMENT | QUESTIONS AND VERIFIED
ANSWERS | ALREADY GRADED A+ | Plus
RATIONALES | BRAND NEW!
Course Name: Texas Vehicle Emissions Inspector Certification Program
(Certified Emissions Inspector — Endorsement E)
Subject: Vehicle Emissions Inspection & Maintenance (I/M) Program —
Texas Department of Public Safety
SECTION 1: PROGRAM FUNDAMENTALS, JURISDICTION & AIR QUALITY
(Questions 1–50)
1. Motor vehicles in Texas are the largest source of which two
pollutants, making the Inspection/Maintenance (I/M) program
essential for air quality management?
A. Sulfur dioxide (SO₂) and particulate matter (PM)
B. Hydrocarbons (HC) and carbon monoxide (CO)
C. Nitrogen (N₂) and oxygen (O₂)
D. Lead (Pb) and ozone (O₃)
❖ Rationale: The Texas DPS Emissions Inspector Study Guide
identifies motor vehicles as the largest source of hydrocarbons
(HC) and carbon monoxide (CO) in Texas. These pollutants are
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primary precursors to ground-level ozone formation and are
directly targeted by the I/M program.
2. Ground-level ozone is formed through an atmospheric reaction
between which two pollutant categories?
A. Carbon monoxide and carbon dioxide
B. Hydrocarbons (HC) and oxides of nitrogen (NOx)
C. Sulfur dioxide and particulate matter
D. Lead and carbon monoxide
❖ Rationale: Ozone is not emitted directly from vehicles but is
formed when HC and NOx react in the presence of sunlight. The
I/M program focuses on reducing these ozone precursors to
achieve federal air quality standards.
3. According to the Texas DPS training materials, a properly
functioning "typical" vehicle emits approximately how much air
pollution annually?
A. 5 pounds
B. 50 pounds
C. About one-half ton
D. Two tons
❖ Rationale: The DPS study guide states that a typical vehicle emits
approximately a half-ton of air pollution per year. A
malfunctioning vehicle can emit many times that amount,
underscoring the importance of regular emissions inspections.
4. What is the primary purpose of the On-Board Diagnostics (OBD II)
system as defined in Texas regulations?
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A. To increase vehicle fuel economy
B. To ensure vehicles emit the minimum amount of pollutants through
their useful life
C. To prevent vehicles from starting when maintenance is overdue
D. To track vehicle mileage for registration purposes
❖ Rationale: The OBD II system is designed to monitor emissions-
related components and ensure the vehicle maintains compliance
with federal emissions standards throughout its operational life.
30 TAC §114.2 defines the OBD system as the computer system
that monitors emissions control equipment performance.
5. Texas emissions testing began in which year and has since evolved
into the current OBD II-based program?
A. 1980
B. 1990
C. 1996
D. 2000
❖ Rationale: According to DPS historical program documentation,
Texas emissions testing began in 1990. The program has evolved
significantly, with OBD II testing becoming the primary method for
1996 and newer vehicles.
6. Which Texas state agency has primary oversight authority for the
vehicle emissions inspection program, including inspector licensing
and station certification?
A. Texas Commission on Environmental Quality (TCEQ)
B. Texas Department of Public Safety (DPS)
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C. Texas Department of Motor Vehicles (TxDMV)
D. Environmental Protection Agency (EPA)
❖ Rationale: The Texas DPS manages the vehicle inspection program,
including emissions testing requirements and inspector licensing.
While TCEQ sets air quality standards, DPS administers the
inspection and certification process.
7. An "affected county" is defined as any Texas county that:
A. Has a population exceeding 500,000 residents
B. Participates in an inspection and maintenance (I/M) program to
reduce harmful emissions from motor vehicles
C. Has been designated by the EPA as having unhealthy air quality for
any pollutant
D. Contains a state-operated vehicle inspection facility
❖ Rationale: The DPS study guide defines an affected county as any
county participating in an I/M program. Vehicles registered in or
primarily operated in these counties are subject to emissions
testing requirements.
8. How many Texas counties currently participate in the emissions
testing program?
A. 5
B. 10
C. 17
D. 25
❖ Rationale: The DPS Emissions Inspector Study Guide identifies 17
affected counties in Texas that participate in the emissions testing
TEXAS VEHICLE EMISSIONS INSPECTOR
LICENSE EXAMINATION — 2026 CERTIFICATION
ASSESSMENT | QUESTIONS AND VERIFIED
ANSWERS | ALREADY GRADED A+ | Plus
RATIONALES | BRAND NEW!
Course Name: Texas Vehicle Emissions Inspector Certification Program
(Certified Emissions Inspector — Endorsement E)
Subject: Vehicle Emissions Inspection & Maintenance (I/M) Program —
Texas Department of Public Safety
SECTION 1: PROGRAM FUNDAMENTALS, JURISDICTION & AIR QUALITY
(Questions 1–50)
1. Motor vehicles in Texas are the largest source of which two
pollutants, making the Inspection/Maintenance (I/M) program
essential for air quality management?
A. Sulfur dioxide (SO₂) and particulate matter (PM)
B. Hydrocarbons (HC) and carbon monoxide (CO)
C. Nitrogen (N₂) and oxygen (O₂)
D. Lead (Pb) and ozone (O₃)
❖ Rationale: The Texas DPS Emissions Inspector Study Guide
identifies motor vehicles as the largest source of hydrocarbons
(HC) and carbon monoxide (CO) in Texas. These pollutants are
,Page 2 of 67
primary precursors to ground-level ozone formation and are
directly targeted by the I/M program.
2. Ground-level ozone is formed through an atmospheric reaction
between which two pollutant categories?
A. Carbon monoxide and carbon dioxide
B. Hydrocarbons (HC) and oxides of nitrogen (NOx)
C. Sulfur dioxide and particulate matter
D. Lead and carbon monoxide
❖ Rationale: Ozone is not emitted directly from vehicles but is
formed when HC and NOx react in the presence of sunlight. The
I/M program focuses on reducing these ozone precursors to
achieve federal air quality standards.
3. According to the Texas DPS training materials, a properly
functioning "typical" vehicle emits approximately how much air
pollution annually?
A. 5 pounds
B. 50 pounds
C. About one-half ton
D. Two tons
❖ Rationale: The DPS study guide states that a typical vehicle emits
approximately a half-ton of air pollution per year. A
malfunctioning vehicle can emit many times that amount,
underscoring the importance of regular emissions inspections.
4. What is the primary purpose of the On-Board Diagnostics (OBD II)
system as defined in Texas regulations?
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A. To increase vehicle fuel economy
B. To ensure vehicles emit the minimum amount of pollutants through
their useful life
C. To prevent vehicles from starting when maintenance is overdue
D. To track vehicle mileage for registration purposes
❖ Rationale: The OBD II system is designed to monitor emissions-
related components and ensure the vehicle maintains compliance
with federal emissions standards throughout its operational life.
30 TAC §114.2 defines the OBD system as the computer system
that monitors emissions control equipment performance.
5. Texas emissions testing began in which year and has since evolved
into the current OBD II-based program?
A. 1980
B. 1990
C. 1996
D. 2000
❖ Rationale: According to DPS historical program documentation,
Texas emissions testing began in 1990. The program has evolved
significantly, with OBD II testing becoming the primary method for
1996 and newer vehicles.
6. Which Texas state agency has primary oversight authority for the
vehicle emissions inspection program, including inspector licensing
and station certification?
A. Texas Commission on Environmental Quality (TCEQ)
B. Texas Department of Public Safety (DPS)
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C. Texas Department of Motor Vehicles (TxDMV)
D. Environmental Protection Agency (EPA)
❖ Rationale: The Texas DPS manages the vehicle inspection program,
including emissions testing requirements and inspector licensing.
While TCEQ sets air quality standards, DPS administers the
inspection and certification process.
7. An "affected county" is defined as any Texas county that:
A. Has a population exceeding 500,000 residents
B. Participates in an inspection and maintenance (I/M) program to
reduce harmful emissions from motor vehicles
C. Has been designated by the EPA as having unhealthy air quality for
any pollutant
D. Contains a state-operated vehicle inspection facility
❖ Rationale: The DPS study guide defines an affected county as any
county participating in an I/M program. Vehicles registered in or
primarily operated in these counties are subject to emissions
testing requirements.
8. How many Texas counties currently participate in the emissions
testing program?
A. 5
B. 10
C. 17
D. 25
❖ Rationale: The DPS Emissions Inspector Study Guide identifies 17
affected counties in Texas that participate in the emissions testing
