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NICET HCI practice questions

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Question 1Plans, Specifications, and Inspection Documentation

When the Standard Specifications and the project Special Provisions both address the same item and conflict, which document generally governs?

  1. The Special Provisions Correct answer.
  2. The plan sheets
  3. The bid schedule
  4. The Standard Specifications

Explanation

Special provisions are written for a specific contract and modify or supplement the standard specifications, so they take precedence over the standard specifications when the two conflict. Plan sheets and the bid schedule are subordinate to the governing specification requirements.

Question 2Plans, Specifications, and Inspection Documentation

What does the profile portion of a plan-and-profile sheet primarily show?

  1. Utility relocation costs
  2. Centerline elevations Correct answer.
  3. Pavement cross sections
  4. Traffic control sequence

Explanation

A profile presents the vertical alignment of the project along the centerline, showing existing and proposed elevations at each station. Cross sections, cost data, and traffic control sequencing are shown on other sheets.

Question 3Plans, Specifications, and Inspection Documentation

What is the primary purpose of the inspector's daily report?

  1. Record work performed and site conditions Correct answer.
  2. Replace the contractor's certified payroll
  3. Satisfy the contractor's QC plan
  4. Serve as the final payment estimate

Explanation

The daily report creates a contemporaneous, factual record of the work performed, labor and equipment present, weather, and site conditions. It supports pay quantities, schedule evaluation, and later dispute resolution.

Question 4Plans, Specifications, and Inspection Documentation

For what purpose is a project benchmark shown on the plans used?

  1. Locating existing utilities
  2. Computing pay quantities
  3. Establishing elevations on the site Correct answer.
  4. Setting traffic control devices

Explanation

Benchmarks are surveyed points of known elevation and location that serve as the reference for all vertical control on the project. Field crews run levels from them to set grades and check construction elevations.

Question 5Plans, Specifications, and Inspection Documentation

Roadway excavation is most commonly measured for payment in which unit?

  1. Square yard of disturbed surface
  2. Linear foot along the centerline
  3. Ton of material hauled away
  4. Cubic yard in the original position Correct answer.

Explanation

Earthwork excavation is normally measured as a volume in its original, in-place condition before removal, using plan or cross-section dimensions. Haul distance and shrinkage or swelling are handled by the specification, not by changing the measurement unit.

Question 6Plans, Specifications, and Inspection Documentation

An inspector finds that a plan dimension conflicts with a specification requirement for the same item. What is the appropriate action?

  1. Apply the less costly interpretation
  2. Note it and let the work proceed silently
  3. Notify the engineer for a ruling Correct answer.
  4. Order the contractor to stop work at once

Explanation

Only the engineer has authority to interpret contract documents and resolve conflicts. The inspector documents the conflict and refers it up the chain so a written determination can be issued.

Question 7Plans, Specifications, and Inspection Documentation

Which document formally authorizes the contractor to begin contract work?

  1. The preconstruction minutes
  2. The bid tabulation
  3. The notice to proceed Correct answer.
  4. The performance bond

Explanation

The notice to proceed is the agency's written authorization establishing the date the contractor may start work and from which contract time is counted. Bid tabs, meeting minutes, and bonds do not start the clock.

Question 8Plans, Specifications, and Inspection Documentation

What is the purpose of as-built (record) drawings?

  1. Document the designer's original intent
  2. Replace the contract specifications
  3. Establish the contractor's bid prices
  4. Show completed work and approved field changes Correct answer.

Explanation

As-built drawings record the actual constructed condition, including locations, dimensions, and approved changes made during construction. They become the reference for future maintenance, permitting, and utility records.

Question 9Plans, Specifications, and Inspection Documentation

A contractor submits a shop drawing for a precast drainage structure. What is the inspector's proper role?

  1. Send it directly to the fabricator
  2. Approve it and authorize fabrication
  3. Review it for contract compliance, then forward Correct answer.
  4. File it without any review

Explanation

The inspector checks the submittal for conformance with the contract documents and transmits it with a recommendation, but approval authority rests with the engineer. Fabrication cannot begin until the engineer's approved submittal is returned.

Question 10Plans, Specifications, and Inspection Documentation

Under typical contract terms, a supplemental agreement is used when a change does what?

  1. Causes a single test to fail
  2. Delays a subcontractor's invoice
  3. Replaces the superintendent
  4. Alters the contract scope or cost substantially Correct answer.

Explanation

A supplemental agreement is a signed bilateral modification used for significant changes to the contract, such as substantial scope or cost revisions or time extensions. Minor field adjustments are normally handled by change order or administrative action instead.

Question 11Plans, Specifications, and Inspection Documentation

A cut section measures 240 square feet at station 10+00 and 360 square feet at station 11+00. Using the average end area method, what is the volume between the stations?

  1. 2,222 cubic yards
  2. 370 cubic yards
  3. 1,111 cubic yards Correct answer.
  4. 833 cubic yards

Explanation

Average end area volume equals the mean of the two end areas times the length between stations: (240 + 360)/2 = 300 square feet, times 100 feet equals 30,000 cubic feet. Dividing by 27 cubic feet per cubic yard gives about 1,111 cubic yards.

Question 12Plans, Specifications, and Inspection Documentation

For certain materials, an agency may accept a manufacturer's certificate of compliance in place of what?

  1. Project sampling and testing Correct answer.
  2. A formal contract modification
  3. The contractor's site safety plan
  4. The monthly pay estimate

Explanation

When the specifications allow it, a certificate of compliance certifies that the material meets the specified requirements and can substitute for project-level sampling and testing. The inspector still verifies that the certificate covers the material actually delivered.

Question 13Plans, Specifications, and Inspection Documentation

Force account records are used to do what?

  1. Pay extra work on a time-and-material basis Correct answer.
  2. Record all equipment the contractor owns
  3. Report the daily workforce on site
  4. Track subcontractor payroll deductions

Explanation

Force account is the agreed method for paying work whose extent cannot be defined in advance, using documented labor hours, equipment hours, and materials at contract-specified rates. Accurate daily documentation of each resource is essential to a valid payment.

Question 14Plans, Specifications, and Inspection Documentation

An inspector observes work that does not conform to the specifications. What is the proper first step?

  1. Notify the contractor and engineer in writing Correct answer.
  2. Accept it if the defect looks minor
  3. Wait for the next progress meeting
  4. Reduce the pay quantity to compensate

Explanation

Nonconforming work must be documented and reported promptly in writing to the contractor and engineer so the engineer can decide on acceptance, correction, or removal. The inspector does not have authority to accept or unilaterally adjust payment for deficient work.

Question 15Plans, Specifications, and Inspection Documentation

On a grading plan, contour lines represent what?

  1. Property ownership boundaries
  2. Lines of equal elevation Correct answer.
  3. Pavement joint layout
  4. Drainage area limits

Explanation

Contours connect points of equal elevation, and the spacing between them indicates the steepness of the slope. They are the primary tool for reading proposed grades and drainage direction from a grading plan.

Question 16Plans, Specifications, and Inspection Documentation

What is the primary support for the quantities shown on a progress payment estimate?

  1. The contractor's original bid estimate
  2. The preconstruction meeting minutes
  3. The project schedule update
  4. Field measurements in the inspector's records Correct answer.

Explanation

Progress payments are built from quantities measured in the field and documented in inspection records, priced at the contract unit prices. Bid estimates and schedules are planning tools, not a basis for payment.

Question 17Plans, Specifications, and Inspection Documentation

What is the typical purpose of a contractor's request for information (RFI)?

  1. Notify the agency of a claim
  2. Clarify contract documents during construction Correct answer.
  3. Request additional payment for delays
  4. Substitute an equal product

Explanation

An RFI is a written request asking the design team to clarify or interpret contract documents so the work can proceed correctly. The response becomes part of the project record and may later support a change if the answer alters the work.

Question 18Plans, Specifications, and Inspection Documentation

Work that is necessary to complete a pay item but is not listed as its own pay item is generally treated how?

  1. Incidental to that pay item Correct answer.
  2. Paid under force account
  3. Added by change order
  4. Held for final payment

Explanation

Unless the specifications create a separate pay item, the labor, materials, and equipment needed to complete a listed item are considered incidental and included in that item's unit price. The inspector should not measure or pay incidental work separately.

Question 19Plans, Specifications, and Inspection Documentation

What does a punch list prepared at substantial completion identify?

  1. Disputes referred to arbitration
  2. Work remaining to be corrected or completed Correct answer.
  3. Pay items still unpaid
  4. Materials that failed testing

Explanation

The punch list is the itemized record of deficient or incomplete work that the contractor must correct before final acceptance. Each entry is tracked until it is verified as complete and closed out.

Question 20Plans, Specifications, and Inspection Documentation

Why should sampling locations be selected on a random basis?

  1. It targets the best quality material
  2. It lets the contractor prepare the sites
  3. It gives every unit an equal chance of selection Correct answer.
  4. It reduces the number of tests needed

Explanation

Random selection makes the sample statistically representative of the lot and prevents bias in choosing where to test. Samples taken from convenient or favorable spots can misrepresent the true quality of the material.

Question 21Plans, Specifications, and Inspection Documentation

Contract time is stated in working days. Under typical specifications, which day is not charged against contract time?

  1. A day when a subcontractor is unavailable
  2. A day when the contractor chooses not to work
  3. A day when weather prevents work as defined in the specifications Correct answer.
  4. A day when the contractor awaits its own material delivery

Explanation

Working days are generally charged whenever weather and site conditions allow the contractor to perform a substantial portion of the work, whether or not the contractor actually works. Only days meeting the specification's definition of unworkable weather, or other excusable delays, are not charged.

Question 22Plans, Specifications, and Inspection Documentation

A pay item's final measured quantity differs greatly from the bid quantity. Under typical contract provisions, what may occur?

  1. The item is deleted entirely
  2. The difference is paid at the engineer's estimate
  3. The unit price may be adjusted per the variation clause Correct answer.
  4. The contractor forfeits payment for the excess

Explanation

Many contracts contain a quantity variation clause allowing the unit price to be adjusted when the final quantity varies beyond a stated percentage from the bid quantity, because the contractor's cost basis has changed. The adjustment is made by contract modification, not unilaterally by the inspector.

Question 23Plans, Specifications, and Inspection Documentation

Groundwater is encountered at a much higher elevation than the plans indicate. What documentation matters most for a differing site condition?

  1. The contractor's internal cost opinion
  2. The designer's original boring logs alone
  3. The as-bid plan quantity
  4. Field measurements and conditions at discovery Correct answer.

Explanation

A differing site condition claim turns on evidence of the actual physical conditions encountered, documented contemporaneously by measurement, observation, and dated records. The contractor must also give the required written notice so the engineer can investigate before conditions change.

Question 24Plans, Specifications, and Inspection Documentation

A contractor files a delay claim. Which records best support the agency's position?

  1. Verbal agreements with the foreman
  2. Undated site photographs
  3. Dated daily reports and project correspondence Correct answer.
  4. The contractor's internal schedules

Explanation

Contemporaneous, dated records such as daily reports, meeting minutes, and written correspondence carry the most weight because they were created as events occurred rather than reconstructed later. They establish what work was possible, what the site conditions were, and what instructions were given.

Question 25Plans, Specifications, and Inspection Documentation

The contractor and the engineer disagree on the measured quantity for a completed pay item. What should the inspector do?

  1. Average the two competing measurements
  2. Defer to the contractor's measurement
  3. Document the disagreement and the basis for each measurement Correct answer.
  4. Omit the item from the current estimate

Explanation

The inspector's duty is to record the facts, including the measurement methods used and the points of disagreement, so the engineer can resolve the issue on the record. Unilaterally choosing, averaging, or omitting quantities removes critical evidence from the file.

Question 26Plans, Specifications, and Inspection Documentation

A plan sheet labels a culvert location as "Station 24+65." What does this station indicate?

  1. A point 246.5 feet from the project beginning
  2. Culvert number 24, offset 65 feet right
  3. A point 2,465 feet from the project baseline start Correct answer.
  4. Elevation 24.65 feet above the project datum

Explanation

Highway stationing is written as a plus-sign format in which the number before the plus is hundreds of feet and the number after the plus is the remaining feet. Station 24+65 therefore equals 2,400 + 65, or 2,465 feet along the baseline. Stations measure horizontal distance along the reference line, not elevation or offset.

Question 27Plans, Specifications, and Inspection Documentation

Which plan view presents the vertical alignment of a roadway, including grades, elevations, and vertical curves?

  1. Profile view Correct answer.
  2. Detail sheet
  3. Typical cross section
  4. Plan view

Explanation

The profile view is drawn as a vertical section along the centerline, so it carries existing and proposed elevations, grades, and vertical curve data. The plan view shows the horizontal layout as seen from above. Cross sections show the shape of the roadway across its width at a given station.

Question 28Plans, Specifications, and Inspection Documentation

What is the purpose of an addendum issued by the agency during the bidding period?

  1. It authorizes the contractor to begin work after award
  2. It records field changes made after construction starts
  3. It modifies the bidding documents and becomes part of the contract Correct answer.
  4. It replaces the special provisions at the preconstruction meeting

Explanation

An addendum clarifies, corrects, or changes the plans, specifications, or proposal while bids are being solicited. Bidders must acknowledge each addendum, and acknowledged addenda become part of the contract documents. Once bids are opened, the same kind of change is handled through the contract change process instead.

Question 29Plans, Specifications, and Inspection Documentation

A plan sheet is drawn at a scale of 1 inch = 50 feet. A feature scales 3.5 inches on the sheet. What is its actual length?

  1. 175 feet Correct answer.
  2. 150 feet
  3. 50 feet
  4. 350 feet

Explanation

Multiply the scaled distance by the scale factor: 3.5 inches times 50 feet per inch equals 175 feet. A scale note states the ratio between a unit measured on the sheet and the true distance it represents. Scaled values are approximate and are superseded by written dimensions.

Question 30Plans, Specifications, and Inspection Documentation

A special provision and the agency's standard specifications state different requirements for the same item. Which requirement governs?

  1. The engineer's verbal clarification at the preconstruction meeting
  2. Whichever requirement sets the stricter test frequency
  3. The special provisions, since they are project-specific Correct answer.
  4. The standard specifications, since they apply statewide

Explanation

Contract documents follow a stated order of precedence in which project-specific documents outrank general ones, so special provisions control over standard specifications. The same hierarchy normally places the plans and special provisions above the standard specifications book. Any conflict should still be resolved in writing so the record is clear.

Question 31Plans, Specifications, and Inspection Documentation

In a specification, what does the word "shall" indicate?

  1. A recommendation the contractor may follow at its option
  2. A mandatory requirement the contractor must meet Correct answer.
  3. A requirement that applies only to the engineer
  4. A requirement enforced only when shown on the plans

Explanation

Specifications use "shall" for mandatory requirements, "should" for advisory guidance, and "may" for permissive options. An inspector can rely on "shall" language as an enforceable obligation. Misreading permissive language as mandatory, or the reverse, leads to improper acceptance or rejection.

Question 32Plans, Specifications, and Inspection Documentation

A plan sheet shows a line labeled "MATCH LINE - SEE SHEET 12." What does this tell the reader?

  1. The feature is paid under a separate item listed on Sheet 12
  2. The work beyond that line continues on Sheet 12 Correct answer.
  3. Sheet 12 shows an alternate design that supersedes this sheet
  4. The contractor must submit a matching shop drawing

Explanation

Match lines break a continuous project into sheet-sized segments, and the referenced sheet picks up the work exactly where the line is drawn. Stationing at the match line is repeated on both sheets so the segments can be aligned. Payment items, by contrast, are identified in the bid schedule and the plans' summary of quantities.

Question 33Plans, Specifications, and Inspection Documentation

The engineer returns a shop drawing stamped "Approved as Noted." What does this mean for the contractor?

  1. The contractor is excused from the specification requirement
  2. Rejected; it must be resubmitted before any work begins
  3. Approved for payment without any further review
  4. Acceptable if the noted corrections are incorporated Correct answer.

Explanation

Standard review stamps distinguish full approval, approval with minor corrections, and rejection with resubmittal required. "Approved as Noted" authorizes proceeding provided the comments are incorporated, without a resubmittal. Approval of a submittal never waives a specification requirement or changes the contract.

Question 34Plans, Specifications, and Inspection Documentation

Which entries belong in an inspector's daily report?

  1. Verbatim minutes of the contractor's internal safety committee meetings
  2. The contractor's bid unit prices and the total bid amount
  3. The agency's annual budget for the project corridor
  4. Weather, work performed, crews present, and quantities placed Correct answer.

Explanation

The daily report is the contemporaneous record of conditions and activities on the site, including weather, workforce and equipment, work performed, quantities placed, and significant events. It supports progress payments, delay analysis, and disputes long after the work is covered. Bid prices and agency budgets are not field observations of construction activity.

Question 35Plans, Specifications, and Inspection Documentation

A pay item is bid as a lump sum. How is its progress documented in the field?

  1. By tracking progress toward completion of the item Correct answer.
  2. By counting each unit delivered and paying for it separately
  3. By charging labor, equipment, and materials on force account
  4. By measuring the completed quantity in its pay unit each day

Explanation

Lump sum items are paid for completing the item as a whole rather than by measured quantity, so the inspector documents the extent of completion at each estimate. Unit price items, in contrast, are documented by measured quantities in the specified pay unit. Force account records apply to extra or changed work performed without an agreed price.

Question 36Plans, Specifications, and Inspection Documentation

A plan sheet shows a small triangle with a number inside, placed near a clouded area of a detail. What does this indicate?

  1. A utility crossing that requires potholing before excavation
  2. A revision to that area, identified by its revision number Correct answer.
  3. A survey control point that requires a reference tie
  4. A pay item whose quantity is estimated in the bid schedule

Explanation

Revision clouds outline the portion of a drawing that has changed, and the numbered triangle is the revision marker tied to a revision block or log. That combination lets field staff confirm they are building from the current sheet. The revision block lists the number, date, and description of each change.

Question 37Plans, Specifications, and Inspection Documentation

What information must accompany a materials sample submitted to the testing laboratory?

  1. The contractor's certified payroll and current insurance certificate
  2. The calibration certificate for the testing equipment used
  3. The engineer's stamped shop drawing and a signed transmittal
  4. Project ID, material source, sampling location, and sample number Correct answer.

Explanation

Sample identification links a test result to a specific project, source, and location in the work so the result can be applied to the right material. Without that traceability the test cannot support acceptance or rejection of any particular lot. Identification is recorded at sampling and carried through the chain of custody to the report.

Question 38Plans, Specifications, and Inspection Documentation

An inspector believes the contractor's grading method will produce an unacceptable result. What is the appropriate action?

  1. Notify the engineer, who can require corrective action Correct answer.
  2. Direct the crew to change the method immediately
  3. Wait until final acceptance to raise the concern
  4. Issue a stop-work order suspending the operation

Explanation

The contractor controls the means and methods of construction, and the engineer administers the contract and directs corrective action. The inspector observes, documents, and reports concerns promptly through the engineer. Raising an issue only at final acceptance lets nonconforming work spread and complicates the remedy.

Question 39Plans, Specifications, and Inspection Documentation

A plan notes that elevations are referenced to NAVD 88. Why does the inspector confirm the datum before checking elevations?

  1. A different datum would express elevations in metric units
  2. Using a different datum shifts all elevations by a constant Correct answer.
  3. NAVD 88 applies only to structures, not earthwork
  4. Datum references expire and must be re-established yearly

Explanation

A datum is the zero reference for a system of elevations, and switching datums changes every elevation by a fixed offset. Checking construction against the wrong datum produces a uniform error that can be mistaken for a grading problem. The inspector therefore ties checks to the datum and benchmark stated in the contract documents.

Question 40Plans, Specifications, and Inspection Documentation

The contractor wants to install a pipe material different from the one named in the specifications. What documentation should exist before installation?

  1. Written approval of the substitution by the engineer Correct answer.
  2. A catalog cut mailed to the agency after installation
  3. Verbal concurrence from the inspector noted in the daily report
  4. A note on the as-built drawings naming the substitute

Explanation

A substitution or approved equal changes the contract requirement and must be authorized in writing by the engineer before the material is used. The request normally includes product data and test results showing equivalence to the specified item. As-built drawings record what was installed; they do not authorize a change.

Question 41Earthwork, Excavation, and Embankment

Compared with the Standard Proctor test, the Modified Proctor test applies greater compactive energy and therefore typically produces:

  1. a higher maximum dry density at a lower optimum moisture content Correct answer.
  2. a lower maximum dry density at a higher optimum moisture content
  3. the same maximum dry density but a flatter compaction curve
  4. a higher optimum moisture content with no change in dry density

Explanation

The Modified Proctor test uses a heavier hammer dropped from a greater height, delivering roughly 4.5 times the energy of the Standard test. The extra energy packs the particles more tightly, which raises the maximum dry density and lets the soil reach that density at a lower water content.

Question 42Earthwork, Excavation, and Embankment

Relative compaction of a compacted fill is expressed as the field dry density divided by which value, multiplied by 100?

  1. the specific gravity of the soil solids
  2. the in-place density of the undisturbed subgrade
  3. the maximum dry density from the laboratory moisture-density test Correct answer.
  4. the wet density of the borrow material

Explanation

Relative compaction compares the density actually achieved in the field with the peak density the same soil can reach under a defined laboratory effort. The denominator is always the laboratory maximum dry density from the applicable Proctor test, and both densities must be on a dry basis.

Question 43Earthwork, Excavation, and Embankment

On a laboratory compaction curve, optimum moisture content is the water content at which:

  1. the soil reaches its liquid limit
  2. the compactive effort is zero
  3. the soil becomes fully saturated
  4. the soil reaches its maximum dry density Correct answer.

Explanation

The compaction curve plots dry density against molding water content, and its peak defines optimum moisture content. At that point the water provides enough lubrication for particles to rearrange into their densest practical arrangement.

Question 44Earthwork, Excavation, and Embankment

Embankment fill is placed and compacted in thin horizontal lifts primarily to:

  1. allow the surface to dry between roller passes
  2. reduce the total quantity of borrow material needed
  3. allow the compactive effort to reach the full depth of each layer Correct answer.
  4. eliminate the need for moisture control

Explanation

Roller energy dissipates rapidly with depth, so a thick layer would be dense at the top and loose below. Keeping lifts thin lets each pass densify the entire layer to a uniform condition before the next lift is placed.

Question 45Earthwork, Excavation, and Embankment

Proofrolling a prepared subgrade is performed to:

  1. increase the dry density of the upper 12 inches
  2. verify the gradation of the subgrade soil
  3. measure the moisture content of the subgrade
  4. find soft, yielding areas that must be corrected before filling Correct answer.

Explanation

A heavily loaded truck is driven over the finished subgrade and the inspector watches for deflection, rutting, or pumping. Those responses reveal weak or unstable spots that must be scarified, dried, or replaced before fill or pavement is placed.

Question 46Earthwork, Excavation, and Embankment

Benching is cut into an existing slope before new fill is placed against it in order to:

  1. improve drainage at the face of the fill
  2. reduce the volume of rock excavation
  3. allow the fill to be placed in thicker lifts
  4. key the new fill into the existing ground so it cannot slide Correct answer.

Explanation

Benching creates a series of horizontal steps that tie the new embankment into the existing slope. Without that keying, the fill can slip along the smooth slope face or along the contact between fill and natural ground.

Question 47Earthwork, Excavation, and Embankment

Under OSHA excavation standards, the maximum allowable slope for a Type C soil excavation is:

  1. 1 1/2 horizontal to 1 vertical Correct answer.
  2. 1 horizontal to 1 vertical
  3. 3/4 horizontal to 1 vertical
  4. 2 horizontal to 1 vertical

Explanation

OSHA assigns progressively flatter permitted slopes as soil quality decreases: 3/4:1 for Type A, 1:1 for Type B, and 1 1/2:1 for Type C. Type C is the least stable class, so it requires the flattest slope of the three.

Question 48Earthwork, Excavation, and Embankment

A silt fence placed downslope of a disturbed area controls erosion by:

  1. filtering water as it flows through the fabric at high velocity
  2. ponding runoff so sediment can settle out before release Correct answer.
  3. chemically treating sediment-laden water
  4. diverting runoff around the site

Explanation

A silt fence is a perimeter sediment barrier; it slows sheet flow and allows a shallow pool to form behind the fabric. Sediment settles in that pool, and water is released slowly through the geotextile.

Question 49Earthwork, Excavation, and Embankment

A field density test is required on a gravelly backfill containing particles up to 1 1/2 inches. The most appropriate method is:

  1. sand cone test with a test hole large enough to hold the coarse particles Correct answer.
  2. nuclear gauge in backscatter mode
  3. laboratory Proctor test on a grab sample
  4. sieve analysis of a disturbed sample

Explanation

The sand cone method physically removes and replaces a known volume of soil, so the test hole can be sized to accommodate coarse particles and give a representative density. Nuclear gauges are affected by coarse fragments and by the chemistry of the material, making them less reliable in this case.

Question 50Earthwork, Excavation, and Embankment

Before a nuclear density gauge is used each day, the technician should:

  1. warm the gauge for at least 4 hours
  2. perform a standard count on the reference block Correct answer.
  3. take a reading on the subgrade and compare it to the laboratory result
  4. recalibrate the gauge against a new Proctor curve

Explanation

The daily standard count verifies that the gauge is operating consistently and detects drift in the detector or electronics. If the standard count falls outside the allowed tolerance, the gauge must be taken out of service until it is repaired and recalibrated.