Mississippi Underground Utilities Examination

Before a Mississippi underground-utilities crew opens an excavation, OSHA 29 CFR 1926.651 first requires the employer to:

• ALocate underground installations and contact the utility owners
• BStockpile all spoil against the near trench wall to form a traffic berm
• CBegin the cut and call utilities only if a line is struck
• DSkip locates when the trench will be less than 5 feet deep

A crew is laying water main in an open-cut trench 6 feet deep and 300 feet long. Applying the OSHA lateral-travel rule for means of egress, what is the smallest number of ladders that will serve the run and how far apart may they stand?

• ATwo ladders, one at each end, because only the ends of a trench need egress
• BSix ladders, spaced no more than 50 feet apart, so no worker is more than 25 feet of late…
• CThree ladders, spaced 100 feet apart, because the lateral-travel rule applies only to tre…
• DNo ladder is required, because the egress rule starts at 20 feet of depth

Unless retaining devices are used, excavated spoil and equipment must be kept at least how far from the edge of an excavation?

• A6 inches
• B12 inches
• C2 feet
• D5 feet

OSHA treats an excavation atmosphere as oxygen-deficient when the oxygen concentration falls below:

• A19.5 percent
• B16.0 percent
• C21.0 percent
• D23.5 percent

Before employees enter an excavation more than 4 feet deep where a hazardous atmosphere could reasonably be expected, OSHA requires the atmosphere to be tested. Flammable gas must not exceed:

• A5 percent of the lower flammable limit
• B10 percent of the lower flammable limit
• C20 percent of the lower flammable limit
• D50 percent of the lower flammable limit

A competent person must inspect an excavation, adjacent areas, and protective systems at least:

• AOnce a week unless the soil looks dry
• BOnly when the trench first exceeds 5 feet
• COnly after a cave-in or near-miss
• DDaily, before each shift, and after every rainstorm or other hazard-increasing event

While a backhoe or crane is handling pipe or a trench box, employees must not:

• AStand under the load of the digging or lifting equipment
• BUse hand signals that the operator can see
• CStay outside the swing radius unless needed for the lift
• DWear a hard hat and high-visibility vest

A protective system (sloping, benching, shoring, or a shield) is required in an excavation unless:

• AThe excavation is entirely in stable rock, or it is less than 5 feet deep and a competent…
• BThe crew is only in the trench for 15 minutes
• CThe trench is less than 8 feet deep in any soil
• DThe contractor has a trench box on another street of the same project

OSHA defines a trench as a narrow excavation in which the depth is generally greater than the width and the width at the bottom is not greater than:

• A4 feet
• B8 feet
• C15 feet
• D20 feet

Unconfined compressive strength of 1.5 tsf or greater is one Type A soil test, but OSHA will not classify the soil as Type A if it is:

• AFissured, subject to vibration, previously disturbed, part of a sloped layered system of…
• BCohesive clay that has never been disturbed
• CStable rock with no cracks
• DAngular gravel that stands in a 1H:1V cut

For a simple slope 20 feet deep or less, OSHA Appendix B maximum allowable slopes are:

• AType A 1H:1V, Type B 1½H:1V, Type C 2H:1V
• BType A ½H:1V, Type B ¾H:1V, Type C 1H:1V
• CType A 3/4H:1V, Type B 1H:1V, Type C 1½H:1V, and stable rock vertical
• DAll soils 1H:1V if a trench box is on site

When timber or hydraulic shoring is used in a utility trench, OSHA practice is to:

• AInstall it from the bottom up and remove it from the top down so the last brace is at the…
• BPull all shores at once with the excavator before any backfill is placed
• CSet only the bottom walers until the pipe is home, then add the rest
• DInstall it from the top down and remove it from the bottom up as backfill is placed

The Mississippi Underground Utilities contractor classification covers installation of:

• AWater, sewer, and gas pipelines plus excavation, grading, and paving
• BOnly sanitary-sewer laterals inside a building
• COnly aerial electric transmission structures
• DOnly interior plumbing fixtures and water heaters

After a water, sewer, or gas pipe is set on bedding in an open-cut trench, the material compacted from the invert up around the haunches and usually to at least the springline (often to 6 to 12 inches over the crown, per the specification) is called:

• AHaunching and initial backfill in the pipe zone
• BThe final wearing course of street pavement
• CUncompacted native spoil dumped in one lift from the top of the trench
• DA surface dressing applied only after traffic is restored

Which set of methods is inside the Mississippi Underground Utilities classification?

• AInterior finish carpentry and cabinet hanging
• BOverhead conductor stringing and pole-top transformer setting
• CDirectional drilling, auger boring, jacking and boring, trenchless installation, wet and…
• DResidential HVAC refrigerant charging

Ductile-iron water main installation is governed in the field primarily by which AWWA standard?

• AANSI/AWWA C600, Installation of Ductile-Iron Mains and Their Appurtenances
• BASTM C76, reinforced concrete pipe manufacture
• CASME B31.1, power piping inside boiler plants
• DNFPA 13, sprinkler-system installation inside buildings

On a ductile-iron water main, the direction the bells face:

• AMust always match the direction of flow or the main will not pass water
• BMust be reversed at every other joint to lock the line
• CMust always face downhill so air can escape the bells
• DIs not functionally related to the direction of flow; bells are often laid facing the dir…

When groundwater stands in a pipe or box-culvert trench, the correct construction response is to:

• ADewater so excavation and pipe laying are done in the dry, and keep pumping through a fil…
• BLay the pipe underwater and skip bedding compaction
• CFlood the trench deeper so the pipe floats into grade
• DIgnore the water if the pipe is gasketed

A helium-neon construction laser is commonly used on sewer and culvert work because it:

• AReplaces the need to check invert elevations after the pipe is home
• BAutomatically compacts the haunch when the beam is centered
• CProjects a continuous, unsagged line-and-grade beam that can be intercepted with a target…
• DIs intended only for setting curb grades, not pipe invert

A rectangular utility trench is 4 feet wide, 6 feet deep, and 135 feet long. What is the excavated volume in cubic yards (use 27 cubic feet per cubic yard)?

• A40 cubic yards
• B80 cubic yards
• C120 cubic yards
• D360 cubic yards

ACPA practice is to start a concrete-pipe run at the outlet end with:

• AThe bell end pointing upstream and the spigot or tongue pointing downstream
• BBells pointing downstream and the first joint made at the upstream manhole
• CRandom bell orientation as long as gaskets are lubricated
• DEvery other pipe reversed so bells lock against each other

When a concrete pipe or box section has lifting holes, the lifting device should:

• AHook only the outside face of the wall so the hole is not used
• BBe a sling dragged under the section while it is rolled
• CBe a chain choker around one bell only
• DPass through the wall and distribute the weight along the inside barrel or inside wall

After concrete pipe is unloaded, ACPA says the sections should be:

• ARolled or lifted, never dragged, and not rolled over rough or rocky ground
• BDragged along the trench bank to save crane time
• CDropped onto old tires from the truck bed
• DStacked on end on the bells to keep the barrels clean

Rubber gaskets and preformed or bulk mastics for concrete pipe should be stored:

• AIn a cool, dry place, clean, away from oil, grease, excessive heat, and direct sun
• BIn open sunlight so they stay warm and flexible
• CSoaked in diesel so they slide onto the spigot
• DOn the hot truck deck next to the fuel cans

After precast box culvert sections have been joined, lift holes should be:

• ALeft open so the box can drain during backfill
• BUsed as grout ports for the entire trench
• CPlugged according to the manufacturer’s recommendation
• DCovered only with loose backfill

In the older ACPA bedding classes still shown in Concrete Pipe and Box Culvert Installation, Class A bedding is:

• AA flat subgrade with little or no shaping under circular pipe only
• BAny crushed stone regardless of thickness or compaction
• CNative soil dumped loosely around the pipe with no haunching
• DA concrete cradle, used only with circular pipe, extending up the sides and with densely…

For circular concrete pipe, ACPA Class B shaped bedding seats the pipe in fine granular fill for a width of at least:

• AOne-tenth of the outside diameter
• BOne-quarter of the outside diameter
• CSix-tenths (0.6) of the outside diameter
• DThe full outside diameter plus 2 feet on each side

ACPA Class C shaped bedding for circular pipe requires the subgrade to fit the lower pipe for at least what width, with trench sidefill then lightly compacted to at least 6 inches above the top of the pipe?

• A50 percent of the outside diameter
• B25 percent of the outside diameter
• C90 percent of the outside diameter
• DThe full trench width to original ground

ACPA Class D bedding is used only with circular pipe and is best described as:

• AA reinforced concrete arch over the pipe
• BA 12-inch crushed-stone cradle compacted to 95 percent Modified Proctor
• CLittle or no care to shape the foundation or fill voids, provided the bed is smooth and t…
• DThe required bedding under every box culvert

ACPA Standard Installations (Types 1 through 4) place loosely dumped, uncompacted bedding directly under the invert because that:

• AIncreases invert bending stress so a heavier wall is required
• BIs required only for Class D circular pipe
• CReplaces the need to compact the haunches
• DSignificantly reduces stresses in the pipe

In an ACPA Standard Installation, which zone around the lower half of the pipe provides significant support and reduces pipe stresses?

• AThe haunch, from the foundation up to the pipe springline
• BOnly the overfill from the crown to finished grade
• CA 6-inch sand lens placed only on top of the crown
• DThe trench wall above the original ground surface

Joints on concrete pipe 24 inches in diameter or smaller can usually be homed with:

• AThe excavator bucket striking the bell face
• BA sledge on the crown of the pipe
• CA bar and wood block used as a lever, after the axis is aligned and the gasket is checked…
• DVibrating the trench wall until the pipe slides home

Using a backhoe or other excavating machine to shove concrete pipe or box sections home is:

• AThe preferred ACPA method for pipe larger than 24 inches
• BRequired so the joint opens to the maximum pull
• CAcceptable if the operator uses the bucket teeth for a point load
• DProhibited as direct contact; use a come-along, winch, or cushioned pull so the machine n…

An infiltration test of a sanitary sewer (ASTM C969) is applicable only when the groundwater table is at least:

• AEven with the invert at the upstream manhole
• B2 feet above the crown of the pipe for the entire test section
• C6 inches above the bedding
• DAt original ground regardless of pipe depth

ACPA’s general-guide trench width for circular concrete pipe is:

• AThe inside diameter plus 6 inches
• BA flat 3 feet for every pipe size
• C1.25 times the outside diameter plus 1 foot (1.25B + 1 ft)
• DTwice the inside diameter with no upper limit

When radius (beveled) concrete pipe is used to negotiate a curve, ACPA alignment is correct when:

• AThe point of curve is set at the downstream end of the last straight pipe
• BThe first radius pipe is laid with the long side on the inside of the curve
• CRadius pipe begins two full lengths before the point of curve
• DThe point of curve is at the midpoint of the last straight pipe and the point of tangent…

Unless a precast box culvert is specifically designed for the construction loads, ACPA requires compacted backfill over the top of at least:

• A6 inches before any equipment crosses
• B3 feet, and in an embankment that cover must extend one span or 3 feet, whichever is larg…
• C12 inches of loose native soil only over the joints
• DThe same depth as the box rise, with no other limit

Just before a precast box is pulled home, ACPA wants a small shovel-width trench in the bedding at the receiving joint because:

• AIt is the designated underdrain for the culvert
• BThe box pulls bedding toward the connection, and trapped material in the joint will keep…
• CIt replaces the 3-inch leveling course under the rest of the box
• DIt is required only when the foundation is rock

DIPRA Type 1 laying condition is:

• AA flat-bottom trench of undisturbed earth with loose backfill
• BPipe bedded to the centerline in compacted granular material
• CA concrete cradle to the springline
• DA shaped rock trench with no cushion under the barrel

DIPRA Type 2 laying condition is a flat-bottom trench of undisturbed earth with backfill:

• ALeft completely unconsolidated to the surface
• BReplaced with lean concrete to the crown
• CCompacted granular to 90 percent Standard Proctor to the top of the pipe
• DLightly consolidated to the centerline of the pipe

Polyethylene encasement on ductile-iron pipe is intended to:

• AFit snug with slack at bells, not be airtight or watertight, and be repaired with polyeth…
• BBe a completely airtight and watertight coating bonded to the iron
• CReplace the need for any backfill around the pipe
• DBe omitted wherever the soil is clay

Push-on joint gaskets for ductile-iron pipe should be stored and selected so that:

• AAny manufacturer’s gasket may be used in any bell because all DI gaskets are interchangea…
• BThey are soaked in motor oil to ease assembly
• CThey stay in a cool place out of sunlight, never contact petroleum, and match the specifi…
• DThey are stored on the hot dashboard of the crew truck

Ductile-iron pipe is lowered into the trench with tongs or slings. It must not be:

• AInspected for dirt and damage before it is lowered
• BSet on a true, even trench bottom that supports the barrel
• CHandled with a nylon sling of adequate capacity
• DPushed off the bank and allowed to fall into the trench

DIPRA Type 3 laying condition beds the pipe in:

• AA 4-inch minimum of loose soil (native excavated material free of rocks, foreign material…
• BCompacted crushed stone to the centerline and 90 percent Proctor to the crown
• CUndisturbed rock with no cushion
• DA reinforced concrete arch

DIPRA Type 4 laying condition beds the pipe in sand, gravel, or crushed stone to a depth of:

• A1/8 of the pipe diameter, 4-inch minimum, with backfill compacted to the top of the pipe…
• B1/2 of the pipe diameter with no compaction
• C2 inches of loose native clay only
• DA full concrete encasement

DIPRA Type 5 laying condition beds the pipe:

• AOn a flat, undisturbed bottom with completely loose backfill
• BIn a 1-inch sand dusting only under the bells
• CTo its centerline in compacted granular material (4-inch minimum under the pipe), then co…
• DDirectly on blasted rock

For 14-inch and larger ductile-iron pipe, DIPRA and AWWA C150 advise that:

• AType 1 is always the most economical laying condition
• BConsideration should be given to using a laying condition other than Type 1
• CThe pipe must be concrete-encased for its full length
• DNo polyethylene encasement may be used