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IMSA Traffic Signal II study materials
IMSA Traffic Signal II study resources

IMSA Traffic Signal II practice questions

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Question 1Signal Design and Plan Reading

Which item is normally shown in the title block of a traffic signal plan sheet?

  1. Detector loop inductance values
  2. Controller offset and split values
  3. Sheet number, date, and revision Correct answer.
  4. Conduit bend radius dimensions

Explanation

The title block identifies the drawing itself, so it carries administrative data such as the project name, sheet number, revision, date, scale, and the designer's and checker's initials. Technical data such as timing values, detector values, and conduit dimensions appear in the notes, schedules, or details, not in the title block.

Question 2Signal Design and Plan Reading

On a vertically mounted three-section vehicular signal head, the lenses are arranged from top to bottom as:

  1. Yellow, red, green
  2. Red, green, yellow
  3. Red, yellow, green Correct answer.
  4. Green, yellow, red

Explanation

The standard vertical arrangement places red at the top, yellow in the middle, and green at the bottom, which keeps the most restrictive indication in the position most visible to approaching drivers. This order is consistent across agencies so drivers respond correctly even when color perception is limited.

Question 3Signal Design and Plan Reading

In a ring-barrier diagram, what does the barrier separate?

  1. Detector zones from controller phase assignments
  2. Movements that conflict with each other Correct answer.
  3. Conduit runs from the cabinet to the pull boxes
  4. Pedestrian intervals from vehicular intervals

Explanation

The barrier divides the diagram into groups of phases that may time concurrently; phases on opposite sides of a barrier conflict and cannot be green at the same time. Phases within the same ring must run in sequence, while phases in different rings between the same barriers may run together.

Question 4Signal Design and Plan Reading

All else being equal, increasing the approach speed used in calculating a yellow change interval will:

  1. Change only the pedestrian clearance time
  2. Lengthen the yellow change interval Correct answer.
  3. Shorten the yellow change interval
  4. Leave the yellow change interval unchanged

Explanation

The yellow interval must cover the distance a driver travels while deciding to stop or clear the intersection, and higher speed means more distance is covered in the same time. The standard kinematic equation therefore produces a longer yellow interval as approach speed increases.

Question 5Signal Design and Plan Reading

A crosswalk is 60 feet long. Using the MUTCD walking speed of 3.5 feet per second, the minimum pedestrian change (flashing DON'T WALK) time is approximately:

  1. 10 seconds
  2. 17 seconds Correct answer.
  3. 30 seconds
  4. 25 seconds

Explanation

The pedestrian change interval is computed by dividing the crossing distance by the walking speed used in design. Dividing 60 feet by 3.5 feet per second yields about 17 seconds, which is the minimum time the flashing DON'T WALK must be displayed.

Question 6Signal Design and Plan Reading

A 120-volt signal circuit carries 3 amperes over a 500-foot one-way run of No. 14 AWG copper with a resistance of about 3.1 ohms per 1000 feet. What is the approximate voltage drop?

  1. About 1.6 volts
  2. About 9.3 volts Correct answer.
  3. About 18.6 volts
  4. About 4.7 volts

Explanation

Voltage drop uses the total conductor length, which is twice the one-way run, so 500 feet out and back is 1000 feet of conductor and about 3.1 ohms. Applying Ohm's law, 3 amperes times 3.1 ohms gives roughly 9.3 volts of drop.

Question 7Signal Design and Plan Reading

Which of the following most directly affects the sensitivity of an inductive loop detector?

  1. The number of turns of wire in the loop Correct answer.
  2. The color of the pavement markings
  3. The length of the conduit run to the cabinet
  4. The mounting height of the signal head

Explanation

Loop sensitivity depends on the inductance change produced when a vehicle occupies the detection zone, and adding turns of wire increases the inductance of the loop. Loop size, shape, and the detector's sensitivity setting also matter, but turn count is a direct design variable.

Question 8Signal Design and Plan Reading

The primary function of the conflict monitor unit in a traffic signal cabinet is to:

  1. Detect vehicle calls at the stop line
  2. Drive the signal to flash when a fault occurs Correct answer.
  3. Provide surge protection for the controller
  4. Store the timing plans for each time of day

Explanation

The conflict monitor watches the field outputs for faults such as conflicting greens, a missing or improper voltage, or a failed driver, and forces the intersection into flashing operation when it detects one. It is a fail-safe watchdog, not a timing or detection device.

Question 9Signal Design and Plan Reading

A flashing yellow arrow left-turn display indicates that:

  1. The signal is operating in flashing mode
  2. Left turns are protected from opposing traffic
  3. Left turns are permitted after yielding Correct answer.
  4. Left turns are prohibited at all times

Explanation

The flashing yellow arrow permits the left turn but requires the driver to yield to opposing through traffic and to pedestrians in the crosswalk. The steady green arrow indicates a protected turn, and the steady red arrow prohibits the turn.

Question 10Signal Design and Plan Reading

Compared with a span-wire installation, a mast arm typically provides:

  1. Shorter span between support points
  2. Lower installation cost at wide intersections
  3. Elimination of the need for a foundation
  4. Greater rigidity and less signal head movement Correct answer.

Explanation

A mast arm is a rigid structure anchored at one end, so the signal heads move far less in wind and are less likely to drift out of alignment. Span-wire installations rely on cable tension and are more susceptible to sway and sag.

Question 11Signal Design and Plan Reading

A plan sheet is drawn at a scale of 1 inch = 20 feet. A conduit run measures 3.5 inches on the plan. What is the actual run length?

  1. 35 feet
  2. 85 feet
  3. 70 feet Correct answer.
  4. 60 feet

Explanation

Each inch on the drawing represents 20 feet in the field, so multiplying 3.5 inches by 20 feet per inch gives 70 feet. Scaling from a plan always uses the stated sheet scale rather than an assumed one.

Question 12Signal Design and Plan Reading

During the permissive portion of a protected/permissive left-turn operation, a left-turning driver must:

  1. Proceed without yielding because the green is circular
  2. Wait for a green arrow before turning
  3. Yield only to pedestrians, not to opposing traffic
  4. Yield to opposing traffic and to pedestrians Correct answer.

Explanation

A permissive left turn is made on a circular green or flashing yellow arrow and requires the driver to yield the right-of-way to opposing through traffic and to pedestrians in the crosswalk. Only the protected portion, shown by a steady green arrow, gives an exclusive right-of-way.

Question 13Signal Design and Plan Reading

In an actuated signal controller, a call is best described as:

  1. The time between the start of green and the start of yellow
  2. A signal from the controller to the conflict monitor
  3. The interval when all signal faces are red
  4. A request for service from a detector or push button Correct answer.

Explanation

A call is stored when a detector, push button, or other input requests service for a phase. The controller holds the call until that phase can be served, subject to the programmed timing parameters.

Question 14Signal Design and Plan Reading

Railroad preemption at a signal near a highway-rail crossing is intended to:

  1. Give pedestrians additional crossing time
  2. Reduce the flash rate of the signal heads
  3. Shorten the cycle length during peak periods
  4. Clear the crossing of vehicles Correct answer.

Explanation

When a train is detected, preemption terminates the normal sequence and moves the signal to a state that clears vehicles off the tracks and prevents new queues from forming across the crossing. The signal is held in that track-clearing state until the train has passed.

Question 15Signal Design and Plan Reading

In a NEMA TS 2 cabinet, communication between the controller unit and the detector racks is typically provided by:

  1. Individual home-run wires for each detector
  2. Fiber optic cable for each detector input
  3. A wireless radio link to the controller
  4. A serial SDLC data link Correct answer.

Explanation

TS 2 architecture uses a serial data link, commonly described as SDLC, to pass detector and unit status information between the controller and the rack-mounted assemblies over a shared bus. This replaces the large bundle of individual detector home runs used in earlier architectures.

Question 16Signal Design and Plan Reading

For a conduit run containing more than two conductors, the NEC limits conductor fill to what percentage of the conduit's interior cross-sectional area?

  1. 25 percent
  2. 53 percent
  3. 40 percent Correct answer.
  4. 31 percent

Explanation

The fill tables allow 53 percent for a single conductor, 31 percent for two conductors, and 40 percent for three or more. Limiting fill preserves the ability to pull conductors without damaging insulation and allows heat to dissipate.

Question 17Signal Design and Plan Reading

Which of the following is one of the MUTCD traffic signal warrants?

  1. Pavement condition rating
  2. Presence of a bus stop
  3. Eight-hour vehicular volume Correct answer.
  4. Street lighting level

Explanation

The MUTCD warrants include the eight-hour vehicular volume warrant, along with warrants based on four-hour volume, peak-hour volume, pedestrian volume, school crossings, coordinated systems, crash experience, roadway network, and proximity to a grade crossing. Pavement condition and lighting levels are not signal warrants.

Question 18Signal Design and Plan Reading

A field review shows that trucks in the right lane block the only signal face from the view of drivers in that lane. The appropriate design response is to:

  1. Increase the yellow change interval
  2. Add a supplemental signal face Correct answer.
  3. Reduce the posted speed limit on the approach
  4. Remove the conflicting pavement markings

Explanation

Every lane approaching a signal must have a continuous view of at least one signal face, so when large vehicles can obscure the sole display, a supplemental face is added for the affected lanes. Speed limit changes and timing adjustments do not correct an obstruction of the display.

Question 19Signal Design and Plan Reading

Two vehicle movements may be timed concurrently in a ring-barrier diagram only if:

  1. They appear in the same ring of the ring-barrier diagram
  2. They are assigned the same phase number by the controller
  3. Their yellow change and all-red intervals are equal
  4. They are in different rings between the same barriers Correct answer.

Explanation

Phases housed in different rings between the same pair of barriers may run at the same time because they are non-conflicting movements. Phases on opposite sides of a barrier, or phases sharing a ring, cannot be green simultaneously.

Question 20Signal Design and Plan Reading

A yellow retroreflective border around a signal face is used to:

  1. Shield the lenses from direct sunlight
  2. Improve conspicuity against a cluttered background Correct answer.
  3. Reduce power consumption of the signal head
  4. Identify the phase number of the display

Explanation

The border, often called a backplate, frames the lenses so the signal stands out from signs, lighting, and other visual clutter behind it. It is especially useful where the background changes with the time of day or season.

Question 21Signal Design and Plan Reading

On a controller timing sheet, the offset is best described as the:

  1. The time the signal remains in flashing operation
  2. The time that elapses from a vehicle call to the start of green
  3. The combined length of the yellow change and all-red intervals
  4. Time from a system reference point to the coordinated green start Correct answer.

Explanation

Offset positions a coordinated phase's green relative to a common system reference point so that platoons arriving from upstream intersections receive a green. It is expressed in seconds and is adjusted whenever the cycle length or progression plan changes.

Question 22Signal Design and Plan Reading

The equipment grounding conductor in a traffic signal cabinet is installed to:

  1. Reduce voltage drop on long detector runs
  2. Carry the signal current back to the controller
  3. Provide a low-impedance path to earth for fault current Correct answer.
  4. Serve as the neutral conductor for 120-volt loads

Explanation

The equipment ground gives fault current a low-impedance path back to the source so overcurrent devices trip quickly, and it gives surge arrestors a reference to divert transient energy. It must never carry normal operating current.

Question 23Signal Design and Plan Reading

Compared with an inductive loop, a video detection system has the advantage that:

  1. Immunity to all weather and lighting conditions
  2. Lower cost of detectors than loops
  3. No electrical power is required at the intersection
  4. Detection zones can be relocated without cutting pavement Correct answer.

Explanation

Video detection zones are drawn in software, so zones can be moved, added, or reshaped when lane assignments change without saw-cutting the pavement. Loops require new saw cuts and splicing for any change in detection geometry.

Question 24Signal Design and Plan Reading

In lead-lag left-turn operation, one direction receives its protected left turn before the opposing through movement and the other after it. A key design concern with this sequence is:

  1. Elimination of the need for an all-red interval
  2. A left-turn trap if drivers misread the display Correct answer.
  3. Inability to use flashing yellow arrow displays
  4. The need for a longer pedestrian walk interval

Explanation

In lead-lag operation an opposed left-turn driver may see a circular green while the opposing left turn is protected, creating a trap if the driver assumes the turn is protected. Careful display selection and signing are needed to keep the sequence from misleading drivers.

Question 25Signal Design and Plan Reading

On a traffic signal plan sheet, the legend is used to:

  1. Show the sequence of construction activities
  2. Define the symbols and abbreviations used on the sheet Correct answer.
  3. List the controller timing values for each phase
  4. Give traffic volume counts used in the design

Explanation

The legend is the key to reading the drawing, translating symbols for poles, pull boxes, conduit, conductors, and detection into their field meaning. Without it, a reader cannot reliably interpret graphical information on the sheet.

Question 26Signal Design and Plan Reading

The title block of a traffic signal plan sheet typically contains which of the following?

  1. The detector channel assignments for each phase
  2. The conduit sizes and conductor counts for each run
  3. The project name, sheet title, and designer's seal Correct answer.
  4. The signal phasing sequence and interval timings

Explanation

The title block is the identification block placed along the edge of every plan sheet; it carries the project name and number, the sheet title and number, the date, and the responsible professional's seal. Technical content such as phasing, conduit schedules, and detector assignments appears in the body of the sheet or on separate detail sheets.

Question 27Signal Design and Plan Reading

In the standard NEMA phase numbering convention, the mainline through movements at a typical four-leg intersection are assigned which phase numbers?

  1. 2 and 6 Correct answer.
  2. 4 and 8
  3. 1 and 5
  4. 3 and 7

Explanation

In the NEMA convention the through movements on the main street are phases 2 and 6, with their opposing left turns as phases 1 and 5. The cross-street through movements are 4 and 8 and the cross-street left turns are 3 and 7.

Question 28Signal Design and Plan Reading

A station callout on a plan reads 12+50. What distance does this represent?

  1. 12,500 feet
  2. 12.5 feet
  3. 1,250 feet Correct answer.
  4. 125 feet

Explanation

Stationing is written in the form of a whole number of 100-foot stations plus a remainder in feet, so the value before the plus sign is multiplied by 100. A station of 12+50 is therefore 1,200 feet plus 50 feet, or 1,250 feet.

Question 29Signal Design and Plan Reading

Match lines on a set of roadway plans are used to:

  1. Show where the work at the edge of one sheet continues on another sheet Correct answer.
  2. Indicate the beginning and end of a conduit run
  3. Show where utility lines cross beneath the roadway
  4. Mark the limits of right-of-way acquisition

Explanation

Match lines are drawn at the edges of a plan sheet with a corresponding station or label so the reader can align the work with the adjacent sheet. They exist because the full project cannot fit on a single sheet at the chosen scale.

Question 30Signal Design and Plan Reading

A plan note along a signal interconnect route reads "3-2 in PVC." What does this mean?

  1. Three 2-inch PVC conduits run in that section Correct answer.
  2. A single 2-inch conduit is buried at a 3-foot depth
  3. The conduit run is 3 feet long with a 2-inch diameter
  4. Three 2-inch conductors are pulled through a single conduit

Explanation

In conduit callouts the leading number is a quantity and the following dimension is the trade size of each conduit, so "3-2 in PVC" denotes three separate 2-inch PVC conduits. Conductors are listed separately in a conductor schedule or cable callout.

Question 31Signal Design and Plan Reading

A crosswalk is 60 feet long and the design walking speed is 3.5 feet per second. What is the minimum pedestrian change (flashing DON'T WALK) interval?

  1. 12 seconds
  2. 21 seconds
  3. 17 seconds Correct answer.
  4. 25 seconds

Explanation

The pedestrian change interval is found by dividing the crossing distance by the walking speed: 60 feet divided by 3.5 feet per second equals about 17.1 seconds, rounded to 17 seconds. The walk interval is added on top of this value.

Question 32Signal Design and Plan Reading

The yellow change interval at a signalized approach is primarily intended to:

  1. Provide time for pedestrians to finish crossing the roadway
  2. Allow a driver who cannot stop comfortably to clear the intersection Correct answer.
  3. Allow vehicles queued at the stop line to begin moving before the green
  4. Separate the green indications of conflicting movements

Explanation

The yellow change interval warns drivers that the green is ending and gives those too close to stop safely the time to travel through the intersection. It is typically set from perception-reaction time plus braking distance for the approach speed.

Question 33Signal Design and Plan Reading

Where signal heads are mounted over the roadway on a span wire or mast arm, the bottom of the signal housing should generally be at least:

  1. 14 feet above the pavement
  2. 15 feet above the pavement Correct answer.
  3. 12 feet above the pavement
  4. 10 feet above the pavement

Explanation

MUTCD guidance calls for the bottom of the signal housing over the roadway to be at least 15 feet above the pavement, with a practical maximum of about 25.5 feet. Mounting lower reduces clearance for tall vehicles; mounting too high degrades visibility of the display.

Question 34Signal Design and Plan Reading

A supplemental near-side signal head is most often added to an approach when:

  1. The posted speed limit on the approach is below 30 mph
  2. The approach has no pedestrian signal heads installed
  3. The far-side signal face could be hidden from drivers stopped close to the stop line Correct answer.
  4. The controller is operating in flashing mode

Explanation

A driver stopped close to the stop bar may lose sight of a far-side signal head under the vehicle roof or header, so a near-side face is added to keep an indication visible. This is a line-of-sight remedy rather than a speed or pedestrian-related requirement.

Question 35Signal Design and Plan Reading

An advance (upstream) detector located several hundred feet ahead of the stop line is typically used to:

  1. Detect vehicles in the opposing left-turn lane
  2. Extend the green for high-speed approaching vehicles Correct answer.
  3. Count pedestrians waiting to cross
  4. Replace the stop-bar loop during off-peak hours

Explanation

Advance detectors give the controller extra warning of a vehicle approaching at high speed, so the green can be extended or a phase can be called before the vehicle reaches the stop bar. Stop-bar detection remains the primary presence detection at the intersection.

Question 36Signal Design and Plan Reading

The cabinet wiring diagram included in a traffic signal plan set is used mainly to:

  1. Show which phases may run at the same time
  2. Show the geometric layout of the intersection
  3. Set the timing values for each signal phase
  4. Identify the terminals and conductors that connect cabinet components Correct answer.

Explanation

A wiring diagram is a schematic of the cabinet's internal electrical connections, identifying terminal blocks, wire numbers, and the conductors that link the controller, load switches, detector racks, and field terminals. It supports installation, troubleshooting, and modification of the cabinet.

Question 37Signal Design and Plan Reading

On an actuated phase, the minimum green interval is set primarily based on:

  1. The posted speed limit of the approach
  2. The expected number of pedestrian calls per hour
  3. The distance from the stop bar back to the farthest detector Correct answer.
  4. The length of the yellow change interval

Explanation

Minimum green must be long enough for vehicles queued between the detector and the stop bar to start up and clear the intersection after the detector is first occupied. The greater the storage distance behind the stop bar, the longer the minimum green needs to be.

Question 38Signal Design and Plan Reading

For a newly constructed signalized intersection, MUTCD requires that each approach with a through movement be provided with at least:

  1. Two primary signal faces aimed at that approach Correct answer.
  2. One primary face plus one supplemental face aimed at that approach
  3. Three signal faces visible from the stop line
  4. One signal face for each through lane on the approach

Explanation

The standard calls for a minimum of two primary signal faces for each through movement on a new or reconstructed approach, which provides redundancy if one face is obscured or fails. Supplemental faces may be added for visibility but do not by themselves satisfy the primary-face requirement.

Question 39Signal Design and Plan Reading

An approach has a design speed of 45 mph (about 66 feet per second). The intersection is 60 feet wide and the design vehicle is 20 feet long. Using the standard clearance formula, the minimum red clearance (all-red) interval is approximately:

  1. 2.4 seconds
  2. 0.9 second
  3. 1.2 seconds Correct answer.
  4. 1.8 seconds

Explanation

Red clearance is computed by adding the intersection width and the vehicle length and dividing by the approach speed: (60 + 20) feet divided by 66 feet per second equals about 1.2 seconds. The resulting value is applied after the yellow change interval.

Question 40Signal Design and Plan Reading

A technician needs to confirm which detector channel is assigned to the southbound left-turn phase. Which part of the plan set should be consulted?

  1. The intersection geometric layout sheet
  2. The signal phasing diagram
  3. The conduit and conductor schedule
  4. The controller input/output assignment sheet Correct answer.

Explanation

Detector channels, along with other field inputs and outputs, are mapped to controller terminals and phases on the input/output assignment sheet. The phasing diagram shows sequence, the conduit schedule shows raceway and wire, and the layout shows geometry; none of these documents records channel assignments.

Question 41Traffic Signal Installation and Construction

What is the minimum vertical clearance between the bottom of a vehicular signal face and the roadway surface when the signal is mounted over the roadway?

  1. 12 ft
  2. 14 ft
  3. 15 ft Correct answer.
  4. 18 ft

Explanation

The MUTCD requires the bottom of a vehicular signal face mounted over a roadway to be at least 15 ft above the pavement. Greater heights are used where oversize loads, future resurfacing, or local policy require additional clearance.

Question 42Traffic Signal Installation and Construction

Under the NEC, what is the minimum cover required for rigid metal conduit installed beneath a public street?

  1. 12 in
  2. 24 in Correct answer.
  3. 6 in
  4. 36 in

Explanation

NEC Table 300.5 sets the minimum cover beneath streets, highways, roads, alleys, driveways, and parking lots at 24 in for rigid metal conduit and Schedule 80 PVC. Deeper cover is sometimes specified where future excavation or frost conditions warrant it.

Question 43Traffic Signal Installation and Construction

What is the maximum mounting height above the sidewalk for a pedestrian pushbutton?

  1. 60 in
  2. 72 in
  3. 30 in
  4. 42 in Correct answer.

Explanation

Pedestrian pushbuttons are mounted at a maximum of 3.5 ft (42 in) above the sidewalk surface so they can be reached by wheelchair users and children. The MUTCD guidance is applied together with accessibility requirements for operable parts.

Question 44Traffic Signal Installation and Construction

What is the minimum height above the sidewalk for the bottom of a pedestrian signal head?

  1. 5 ft
  2. 6 ft
  3. 7 ft Correct answer.
  4. 4 ft

Explanation

The MUTCD requires the bottom of a pedestrian signal head to be at least 7 ft above the sidewalk so pedestrians, including those who are tall or carrying loads, do not strike it. Greater heights are often used where vehicle overhang is possible.

Question 45Traffic Signal Installation and Construction

What is the maximum total amount of bending permitted in a conduit run between pull points?

  1. 180 degrees
  2. 360 degrees Correct answer.
  3. 720 degrees
  4. 90 degrees

Explanation

The NEC limits the combined bends between boxes or pull points to 360 degrees, the equivalent of four quarter bends. Exceeding this makes conductors difficult or impossible to pull without damage.

Question 46Traffic Signal Installation and Construction

What is the minimum length of a ground rod used as a grounding electrode for a signal cabinet?

  1. 8 ft Correct answer.
  2. 4 ft
  3. 6 ft
  4. 10 ft

Explanation

NEC 250.52 requires rod and pipe electrodes to be at least 8 ft long, typically 5/8-in copper-clad steel driven vertically. Longer rods are used where soil conditions make the required resistance difficult to achieve.

Question 47Traffic Signal Installation and Construction

Which cable type is standard for inductive-loop lead-in from the roadway to the cabinet?

  1. Untwisted, unshielded two-conductor cable with 18 AWG conductors
  2. Twisted, shielded two-conductor cable of 14 AWG Correct answer.
  3. Single-conductor shielded cable with a 10 AWG conductor
  4. Four-conductor shielded cable of 12 AWG, untwisted

Explanation

Loop lead-in cable is twisted to cancel interference picked up along the run and shielded to drain electrical noise, with 14 AWG conductors sized for the loop circuit. The shield is grounded at the cabinet end only.

Question 48Traffic Signal Installation and Construction

What is the minimum conductor size typically specified for wiring inside a vehicular signal head?

  1. 18 AWG
  2. 8 AWG
  3. 10 AWG
  4. 14 AWG Correct answer.

Explanation

Signal head and signal cable conductors are conventionally 14 AWG, which provides adequate mechanical strength and current capacity for lamp or LED loads. Smaller conductors are not permitted for field signal wiring.

Question 49Traffic Signal Installation and Construction

In a traffic signal controller cabinet, how are the service neutral and the equipment grounding conductors terminated?

  1. On separate, isolated terminal bars Correct answer.
  2. They are left unconnected inside the cabinet
  3. On the same terminal bar, bonded to the cabinet
  4. On the cabinet door hinge stud

Explanation

The grounded (neutral) conductor is landed on an isolated terminal bar so it is not bonded to the cabinet, while equipment grounding conductors land on a bar bonded to the enclosure and grounding electrode. Keeping the two separated prevents objectionable current on the cabinet and conduit system.

Question 50Traffic Signal Installation and Construction

Where a conduit run crosses a bridge deck joint, what must be installed to accommodate movement?

  1. A pull box on each side of the joint
  2. A reducing bushing at the joint
  3. A rigid coupling at the joint
  4. An expansion fitting at the joint Correct answer.

Explanation

Bridge joints move with temperature and traffic loading, so an expansion fitting is installed to absorb that movement without shearing the conduit or its conductors. Bonding jumpers are typically added across the fitting to maintain electrical continuity.