TRAFFIC ENGINEER EXAMINATION
100 PRACTICE QUESTIONS WITH ANSWERS AND
RATIONALES
2026–2027 TESTING CYCLE
SECTION 1: PLANNING (Questions 1–28)
Question 1: A traffic impact study (TIS) for a proposed development must include all of the
following EXCEPT:
Answer: Detailed structural design of roadway pavement sections.
Rationale: A traffic impact study focuses on analyzing the transportation impacts of a proposed
development, including trip generation, distribution, assignment, and level of service analysis. It
does not include detailed structural design, which is part of roadway design engineering. The
essential elements of a TIS include existing conditions analysis, trip generation, trip distribution,
trip assignment, and mitigation measures.
Question 2: The formula used to estimate future traffic volumes based on current traffic counts
and growth factors is:
Answer: Future Volume = Current Volume × (1 + Growth Rate)^Years.
,Rationale: This compound growth formula is the standard method for projecting future traffic
volumes. The growth rate is typically based on historical trends, land use projections, or
regional transportation plans. This is a fundamental technique in traffic planning and impact
analysis.
Question 3: Level of Service (LOS) for a signalized intersection is determined based on:
Answer: Average control delay per vehicle (seconds/vehicle).
Rationale: For signalized intersections, LOS is based on average control delay per vehicle. LOS
A represents the best conditions (≤10 sec/vehicle), while LOS F represents the worst (>80
sec/vehicle). For unsignalized intersections, LOS is based on average total delay. For freeway
segments, LOS is based on density (pc/mi/ln).
Question 4: Trip generation is the process of estimating:
Answer: The number of vehicle trips that will be produced by a specific land use.
Rationale: Trip generation is the first step in the four-step travel demand modeling process. It
estimates the number of trips (vehicle trips, person trips, or transit trips) that will be generated
by a specific land use based on its characteristics (e.g., square footage, number of dwelling
units, employees).
,Question 5: Which of the following is NOT a typical input to a travel demand model?
Answer: Pavement structural number.
Rationale: Travel demand models typically use inputs such as land use data, demographic data,
socioeconomic data, transportation network characteristics, and trip generation rates. Pavement
structural number is a design parameter for roadway pavement and is not used in travel demand
modeling.
Question 6: Vehicle Miles Traveled (VMT) is calculated as:
Answer: The sum of the product of vehicle trips and trip lengths.
Rationale: VMT is a measure of total vehicle travel and is calculated as the sum of (number of
trips × trip length) for all trips in a given area or time period. VMT is increasingly used as a
metric for transportation planning and environmental analysis, particularly under SB 743 in
California.
Question 7: A transportation demand management (TDM) strategy is designed to:
Answer: Reduce travel demand by encouraging alternative modes and reducing single-
occupancy vehicle trips.
Rationale: TDM strategies aim to manage travel demand rather than simply increase supply.
Common TDM measures include carpooling/vanpooling programs, transit subsidies, flexible
, work schedules, telecommuting, and parking management. These strategies help reduce
congestion, VMT, and emissions.
Question 8: The 15th percentile speed is commonly used for:
Answer: Establishing speed limits on roadways.
Rationale: The 85th percentile speed is used as the basis for establishing speed limits, as it
represents the speed at or below which 85% of vehicles are traveling. The 15th percentile speed
is sometimes used for determining minimum speed limits or for evaluating slow-moving vehicles.
Speed limit setting is based on the 85th percentile speed, not the 15th percentile.
Question 9: Parking generation rates are typically expressed as:
Answer: Parking spaces per unit of land use (e.g., spaces per 1,000 sq ft of gross floor area).
Rationale: Parking generation rates are used to estimate parking demand for proposed
developments. They are typically expressed as the number of parking spaces required per unit of
land use, such as spaces per 1,000 sq ft of gross floor area for retail, spaces per dwelling unit for
residential, or spaces per room for hotels.
Question 10: The four steps of the traditional travel demand modeling process, in order, are:
Answer: Trip generation, trip distribution, mode choice, trip assignment.
100 PRACTICE QUESTIONS WITH ANSWERS AND
RATIONALES
2026–2027 TESTING CYCLE
SECTION 1: PLANNING (Questions 1–28)
Question 1: A traffic impact study (TIS) for a proposed development must include all of the
following EXCEPT:
Answer: Detailed structural design of roadway pavement sections.
Rationale: A traffic impact study focuses on analyzing the transportation impacts of a proposed
development, including trip generation, distribution, assignment, and level of service analysis. It
does not include detailed structural design, which is part of roadway design engineering. The
essential elements of a TIS include existing conditions analysis, trip generation, trip distribution,
trip assignment, and mitigation measures.
Question 2: The formula used to estimate future traffic volumes based on current traffic counts
and growth factors is:
Answer: Future Volume = Current Volume × (1 + Growth Rate)^Years.
,Rationale: This compound growth formula is the standard method for projecting future traffic
volumes. The growth rate is typically based on historical trends, land use projections, or
regional transportation plans. This is a fundamental technique in traffic planning and impact
analysis.
Question 3: Level of Service (LOS) for a signalized intersection is determined based on:
Answer: Average control delay per vehicle (seconds/vehicle).
Rationale: For signalized intersections, LOS is based on average control delay per vehicle. LOS
A represents the best conditions (≤10 sec/vehicle), while LOS F represents the worst (>80
sec/vehicle). For unsignalized intersections, LOS is based on average total delay. For freeway
segments, LOS is based on density (pc/mi/ln).
Question 4: Trip generation is the process of estimating:
Answer: The number of vehicle trips that will be produced by a specific land use.
Rationale: Trip generation is the first step in the four-step travel demand modeling process. It
estimates the number of trips (vehicle trips, person trips, or transit trips) that will be generated
by a specific land use based on its characteristics (e.g., square footage, number of dwelling
units, employees).
,Question 5: Which of the following is NOT a typical input to a travel demand model?
Answer: Pavement structural number.
Rationale: Travel demand models typically use inputs such as land use data, demographic data,
socioeconomic data, transportation network characteristics, and trip generation rates. Pavement
structural number is a design parameter for roadway pavement and is not used in travel demand
modeling.
Question 6: Vehicle Miles Traveled (VMT) is calculated as:
Answer: The sum of the product of vehicle trips and trip lengths.
Rationale: VMT is a measure of total vehicle travel and is calculated as the sum of (number of
trips × trip length) for all trips in a given area or time period. VMT is increasingly used as a
metric for transportation planning and environmental analysis, particularly under SB 743 in
California.
Question 7: A transportation demand management (TDM) strategy is designed to:
Answer: Reduce travel demand by encouraging alternative modes and reducing single-
occupancy vehicle trips.
Rationale: TDM strategies aim to manage travel demand rather than simply increase supply.
Common TDM measures include carpooling/vanpooling programs, transit subsidies, flexible
, work schedules, telecommuting, and parking management. These strategies help reduce
congestion, VMT, and emissions.
Question 8: The 15th percentile speed is commonly used for:
Answer: Establishing speed limits on roadways.
Rationale: The 85th percentile speed is used as the basis for establishing speed limits, as it
represents the speed at or below which 85% of vehicles are traveling. The 15th percentile speed
is sometimes used for determining minimum speed limits or for evaluating slow-moving vehicles.
Speed limit setting is based on the 85th percentile speed, not the 15th percentile.
Question 9: Parking generation rates are typically expressed as:
Answer: Parking spaces per unit of land use (e.g., spaces per 1,000 sq ft of gross floor area).
Rationale: Parking generation rates are used to estimate parking demand for proposed
developments. They are typically expressed as the number of parking spaces required per unit of
land use, such as spaces per 1,000 sq ft of gross floor area for retail, spaces per dwelling unit for
residential, or spaces per room for hotels.
Question 10: The four steps of the traditional travel demand modeling process, in order, are:
Answer: Trip generation, trip distribution, mode choice, trip assignment.
