CSLB C-12 Earthwork and Paving (Trade Exam) — All Questions

How long should traffic stay off new porous asphalt according to the EPA fact sheet?

• a.24 to 48 hours✓
• b.12 to 18 hours
• c.60 to 90 days
• d.3 to 4 weeks

The EPA fact sheet says contractors should avoid vehicular traffic for 24 to 48 hours after installing porous asphalt. Twelve to 18 hours is shorter than the fact sheet advises, and 3 to 4 weeks and 60 to 90 days are far longer.U.S. EPA, Stormwater BMP: Permeable Pavements

Within what time should pervious concrete be poured after mixing, unless admixtures extend the handling time?

• a.1 hour✓
• b.3 hours
• c.24 hours
• d.15 minutes

The EPA fact sheet says to pour pervious concrete within 1 hour of mixing because of its lower water content, unless admixtures extend the handling time. Three hours and a day are too long, and 15 minutes is the time within which the concrete is typically consolidated after placement.U.S. EPA, Stormwater BMP: Permeable Pavements

A sidewalk has no adjacent curb. At what interval are expansion joints constructed, and how are contraction joints patterned?

• a.200-foot expansion joints; contraction panels of 50 square feet
• b.5-foot expansion joints; contraction panels of 2 to 4 square feet
• c.60-foot expansion joints; panels of 12 to 20 square feet✓
• d.20-foot expansion joints; contraction panels of 100 square feet

Expansion joints are at 60-foot intervals where there is no adjacent curb, and contraction joints create rectangular patterns of 12 to 20 square feet. Twenty feet is the curb contraction spacing, 200-foot and 5-foot expansion intervals are far too wide or too close, and panels of 50, 100 or 2 to 4 square feet do not match the 12 to 20 square-foot pattern.Caltrans 2024 Standard Specifications §73-3.03

Cold planed asphalt pavement is checked after planing. What must be true of the average planed depth?

• a.Equal to or greater than the depth shown on the plans✓
• b.Exactly 0.03 foot less than the depth shown
• c.It need not be measured on the job
• d.Equal to or less than the depth shown

The average cold planed depth must be equal to or greater than the depth shown, even though individual depths may be adjusted by up to 0.03 foot. Planing shallower than shown leaves the overlay too thick or the profile wrong, and measurement is required.Caltrans 2024 Standard Specifications §39-3.04C(2)

What is the same-shift rule for cold planing?

• a.Plane, pave and open to traffic in the same work shift✓
• b.Plane one week and pave during the next week
• c.Plane at night and pave in the following month
• d.Leave the planed surface open until the first rain

Planing is scheduled so that the pavement is planed, the HMA placed and the area opened to traffic in the same work shift; if not, a temporary HMA taper is built and a corrective action plan is submitted. The other schedules leave a drop-off and loose surface under traffic.Caltrans 2024 Standard Specifications §39-3.04A

How far behind the planer may the removal of cold planed material lag?

• a.No more than 500 feet
• b.No more than 5 feet
• c.No more than 50 feet✓
• d.Until the shift ends

Planed material is removed concurrently, with removal not lagging more than 50 feet behind the planer. Five feet is impractical, and 500 feet and end-of-shift removal leave debris on the roadway.Caltrans 2024 Standard Specifications §39-3.04C(3)

A drop-off between existing pavement and a planed area at a transverse joint cannot be avoided before opening to traffic. What is built?

• a.A temporary hot mix asphalt taper✓
• b.A warning sign, because drops under 3 inches are permitted
• c.A vertical wooden bulkhead
• d.A row of cones

A temporary HMA taper to the level of the existing pavement is built and completely removed before the permanent surfacing. Cones or a sign do not remove the drop, a bulkhead is a hazard, and no 3-inch exception exists.Caltrans 2024 Standard Specifications §39-3.04C(4)

How deep is the saw cut at concrete contraction joints before removing part of a curb, sidewalk or driveway for repair?

• a.At least 1/4 inch deep
• b.A saw cut of 1/2 inch
• c.At least 6 inches deep
• d.At least 1-1/2 inches✓

At contraction joints a true line is saw cut at least 1-1/2 inches deep before concrete removal. A quarter inch and a half inch are too shallow to give a clean edge, and 6 inches exceeds the stated depth.Caltrans 2024 Standard Specifications §73-10.03

A rectangular patch of 8 feet by 10 feet is replaced with 3 inches of compacted hot mix weighing 145 pounds per cubic foot. About how many tons are needed?

• a.2.9 tons
• b.14.5 tons
• c.0.73 ton
• d.1.45 tons✓

The volume is 80 × 0.25 = 20 cubic feet, the weight is 20 × 145 = 2,900 pounds, and 2,900 ÷ 2,000 = 1.45 tons. The 2.9 figure divides by 1,000, 14.5 shifts the decimal, and 0.73 halves the thickness.Estimating practice (patch tonnage)

What is the permissible exposure limit for respirable crystalline silica in construction under Cal/OSHA?

• a.25 milligrams per cubic meter, 8-hour average
• b.500 micrograms per cubic meter, 8-hour average
• c.5 micrograms per cubic meter, 15-minute average
• d.50 micrograms per cubic meter, 8-hour average✓

The PEL is 50 micrograms per cubic meter calculated as an 8-hour TWA. Twenty-five milligrams and 500 micrograms are the wrong magnitude, 5 micrograms over 15 minutes is the wrong value and averaging time, and 25 micrograms per cubic meter is the threshold below which the standard does not apply, not the PEL.8 CCR §1532.3

What happens to the detectable warning surface when a curb ramp is removed for repair?

• a.It is omitted if the new ramp is under 6 feet long
• b.It is repainted yellow and left in place on the ramp
• c.It is left in place and the new concrete poured over it
• d.It is removed with the concrete and a new one installed✓

Removal of concrete includes removal of detectable warning surfaces, and a prefabricated surface is installed on the new ramp under the manufacturer's instructions. Burying, painting or omitting it would leave a non-compliant ramp.Caltrans 2024 Standard Specifications §73-10.03

Which feature must a cold planing machine have to control dust and emissions?

• a.A fan that blows the dust to the lane edge
• b.A diesel burner to soften the pavement ahead
• c.A dust-control system, with no fumes or smoke produced✓
• d.A water spray used when neighbors complain

The planing machine must effectively control dust and be operated so that no fumes or smoke are produced, and heating devices are not used. Blowing dust aside is not control, a burner makes fumes and is not allowed, and spraying water only after complaints is not effective control.Caltrans 2024 Standard Specifications §39-3.04C(1)

If the State withholds payment for chip seal work without permanent stripes and markings after the allowed time, how much is withheld?

• a.All remaining payment on the whole contract
• b.5 percent of the whole contract value
• c.50 percent of the estimated value of the unmarked work✓
• d.1 percent per day of the contract value

The Department withholds 50 percent of the estimated value of the completed chip seal work that has not received permanent stripes and markings. All remaining payment, 5 percent of the whole contract and 1 percent per day are not the amount; the withholding is 50 percent and applies only to the unmarked work.Caltrans 2024 Standard Specifications §37-2.01C(1)

HMA is placed on a shoulder less than 5 feet wide outside the traveled way. What equipment is allowed?

• a.A full-width paver with a heated screed and MTV
• b.No hot mix may be placed on narrow shoulders
• c.Hand tools, spread in layers under 1 inch thick
• d.Equipment other than a paver, if finish is uniform✓

On areas less than 5 feet wide outside the traveled way, including shoulders, HMA may be placed in one or more layers with mechanical equipment other than a paver, provided the result is uniformly smooth and textured. A paver with a heated screed and MTV is not mandatory on such narrow areas, hand tools in thin layers are not the only permitted method, and hot mix may be placed on narrow shoulders.Caltrans 2024 Standard Specifications §39-2.01C(1)

On a two-lane road under one-way traffic control, how long must pilot cars route traffic over a new chip seal before the lane opens to uncontrolled traffic?

• a.A minimum of 2 hours✓
• b.A minimum of 24 hours
• c.A minimum of 7 days
• d.At least 5 minutes of travel

After final rolling, traffic is controlled with pilot cars and routed over the new chip seal for a minimum of 2 hours before opening the lane to traffic not controlled with pilot cars. Five minutes is too short for the seal to set, and 24 hours and 7 days are far longer than the stated minimum.Caltrans 2024 Standard Specifications §37-2.01C(4)(d)(ii)

Which classification covers applying directional lines, buttons, markers and arrows on a parking facility surface?

• a.C-12 Earthwork and Paving Contractor
• b.C-34 Pipeline Contractor, trench surfacing
• c.C-32 Parking and Highway Improvement✓
• d.C-27 Landscaping Contractor, grading

The C-32 definition includes directional lines, buttons, markers, signs and arrows on the horizontal surface of a parking facility or roadway, but not re-paving. C-12 lays the pavement, C-34 covers pipeline trenching and its incidental surfacing, and C-27 is landscaping and its grading.CSLB C-32 classification text

Seal coat work will restrict parking on a street. At what spacing are the No Parking - Tow Away signs posted?

• a.At 1,000-foot intervals on the affected streets
• b.At 100-foot intervals on the affected streets✓
• c.At the two ends of the affected street
• d.One sign per block

Signs are posted at 100-foot intervals on the affected streets and must state the dates and hours of the restriction. Signs at 1,000-foot intervals leave long gaps, signs only at the two ends leave the middle of the street unmarked, and one sign per block ignores the 100-foot interval on long blocks.Caltrans 2024 Standard Specifications §37-1.03A

Before traffic or equipment is allowed on concrete pavement (apart from sawing), what strength must it have?

• a.A compressive strength of at least 100 psi
• b.A modulus of rupture of at least 50 psi
• c.A cure time of 24 hours, with no strength test
• d.A modulus of rupture of at least 550 psi✓

Traffic and equipment are kept off until the concrete has attained a modulus of rupture of 550 psi (or the equivalent strength by maturity), with narrow exceptions for sawing and tracked paving equipment at 350 psi. A 100 psi compressive strength and a 50 psi modulus are far too low, and a fixed 24-hour wait without a strength test is not the criterion.Caltrans 2024 Standard Specifications §40-1.03J

Which street sweepers does the State specification allow for sweeping?

• a.A water truck flushing the sediment into the gutter
• b.A steel-broom truck, followed by water flushing
• c.Hand brooms, with the sweepings left in the gutter
• d.Mechanical plus vacuum, vacuum dry, or regenerative-air✓

The specification allows a mechanical sweeper followed by a vacuum-assisted sweeper, a vacuum-assisted dry (waterless) sweeper or a regenerative-air sweeper, and requires at least one on site whenever sweeping is required. Brooms alone and flushing with water do not collect fine sediment.Caltrans 2024 Standard Specifications §13-7.02C

A crew works 30 working days on one project. What is the minimum number of tailgate safety meetings under the 10-working-day rule?

• a.30
• b.6
• c.3✓
• d.1

Meetings are required at least every 10 working days, so 30 ÷ 10 = 3. One meeting does not meet the interval, 6 would be every 5 working days, and 30 would be a meeting every day.8 CCR §1509(e)

Below what level of exposure to respirable crystalline silica does the Cal/OSHA construction silica standard not apply?

• a.50 micrograms per cubic meter, instantaneous peak
• b.25 micrograms per cubic meter, 8-hour average✓
• c.250 micrograms per cubic meter, 8-hour average
• d.2.5 milligrams per cubic meter, 8-hour average

The standard applies except where exposure will remain below 25 micrograms per cubic meter as an 8-hour TWA, which is the action level; the PEL is 50. A 50-microgram instantaneous peak is the wrong averaging time, and 250 micrograms and 2.5 milligrams are far above the 25-microgram threshold.8 CCR §1532.3(a)

When must shade be present for outdoor workers?

• a.If workers request it in writing first
• b.When the temperature reaches 95°F or above
• c.When the outdoor temperature exceeds 80°F✓
• d.On the first day of a forecast heat wave

Shade must be present when the temperature exceeds 80°F, enough for the workers on rest or recovery periods to sit in normal posture without touching. The 95°F figure begins the high-heat procedures, a written request is not a condition for shade, and a first-day heat-wave rule does not exist.8 CCR §3395(d)

At 96°F, what rest period does the heat standard require for an employee?

• a.A ten-minute cool-down rest every two hours✓
• b.Extra drinking water in place of a rest period
• c.A five-minute rest once every eight hours worked
• d.A thirty-minute rest every four hours worked

At 95°F and above the employer ensures a minimum ten-minute net preventative cool-down rest period every two hours as part of the high-heat procedures. Water alone does not replace the rest period, and one five-minute rest in eight hours or a thirty-minute rest every four hours do not match the order.8 CCR §3395(e)

A crew of 12 works an 8-hour shift with no plumbed water. How much drinking water must be on hand at the start of the shift, at one quart per employee per hour?

• a.8 quarts (2 gallons)
• b.48 quarts (12 gallons)
• c.96 quarts (24 gallons)✓
• d.12 quarts (3 gallons)

12 × 8 = 96 quarts, which is 24 gallons. Twelve is one quart per person, 8 is one quart per hour for one person, and 48 is half the requirement.8 CCR §3395(c)

When must vehicles be checked for brakes, tires, horn, steering, seat belts and safety devices?

• a.At the beginning of every single working shift✓
• b.Once a year, at registration renewal
• c.After an accident or a breakdown
• d.When the operator reports a problem

All vehicles in use are checked at the beginning of each shift for service, parking and emergency brakes, tires, horn, steering, coupling devices, seat belts, controls and safety devices, and defects are corrected before the vehicle is used. A yearly or after-the-fact check is too infrequent.8 CCR §1593(d)

What does the noise order require when sound levels exceed the permissible exposure table?

• a.Feasible controls first; ear protection if they fail✓
• b.Hearing tests during the first month of exposure
• c.A warning sign at the machine
• d.Ear protection first, then engineering controls if needed

When levels exceed the table, feasible administrative or engineering controls are used, and if they do not bring sound within the table, the employer provides ear protection and requires its use. Hearing tests do not reduce the exposure, a sign alone does not control the noise, and putting ear protection ahead of feasible controls reverses the order.8 CCR §5096(b); §1521

What does Cal/OSHA require about first-aid kits on a construction project?

• a.A kit stored in the locked job-site office
• b.A kit is not required when a clinic is within a mile
• c.A kit if more than 100 employees are present
• d.A weatherproof container holding at least one kit✓

Every employer working on a construction project provides at least one first-aid kit in a weatherproof container, inspected regularly so expended items are replaced. Head-count thresholds, locked storage and nearby clinics are not exceptions.8 CCR §1512(c)

What size of fire extinguisher must be accessible to a fueling area?

• a.An extinguisher is not needed when fueling outdoors
• b.A small 1-pound extinguisher in the truck
• c.A water-type extinguisher kept near the fuel tank
• d.A dry chemical or CO2 extinguisher rated 6:BC or larger✓

A dry chemical or carbon dioxide extinguisher rated 6:BC or larger must be in a location accessible to the fueling area. Fueling outdoors does not remove the duty, a small unrated unit lacks the rating, and water on a fuel fire can spread it.8 CCR §1594(h)

Temporary covers for trenches in roadways must be designed to carry how much load?

• a.One-half of the maximum intended vehicle load
• b.Only the weight of pedestrians and light tools
• c.The maximum intended vehicle load
• d.At least twice the maximum intended vehicle live load✓

Temporary covers for conduits, trenches and manholes in roadways and vehicular aisles must carry at least 2 times the maximum intended vehicular live load and be installed to prevent displacement. The other loads are inadequate.8 CCR §1597(k)

A boom-type crane will work near a 30,000-volt overhead line. What is the minimum clearance for the boom?

• a.16 feet
• b.6 feet
• c.10 feet✓
• d.4 feet

For lines from 600 up to 50,000 volts, boom-type lifting equipment and storage must keep 10 feet; 6 feet is the general clearance for the same band, and 16 feet applies above 345,000 volts. Four feet is below any clearance.8 CCR §2946, Table 2

May a loader bucket be used to lift an employee to a work area?

• a.No, unless it has equivalent fall protection✓
• b.Yes, if the bucket is empty and held a foot off the ground
• c.It is acceptable at slow speed when the operator is careful
• d.It is acceptable when the engine is off and the bucket is chocked

Buckets, scoops, blades and similar attachments that lack equivalent fall protection may not be used as work platforms or to elevate or transport employees. Care, an empty bucket or a stopped engine do not substitute for the protection.8 CCR §1593(m)

A 0.7-acre driveway job is part of a 12-acre subdivision being built under a common plan of development. Is stormwater permit coverage needed?

• a.Yes, once the driveway has been paved with asphalt
• b.No; driveway work is exempt from the stormwater permit
• c.No; the job itself is under the one-acre threshold
• d.Yes; it belongs to a common plan over one acre✓

The order covers sites under one acre that are part of a larger common plan of development or sale that disturbs more than one acre. Size alone does not exempt it, driveways are not exempt, and coverage does not depend on whether the driveway is paved with asphalt.SWRCB Order WQ 2022-0057-DWQ

Within what time before a forecasted qualifying precipitation event must a QSP inspect areas of concern?

• a.Within 7 days before the event begins
• b.Within 72 hours before the event✓
• c.Within 1 hour before the event begins
• d.After the event has ended

A QSP inspects within 72 hours prior to a forecasted qualifying precipitation event (up to 120 hours ahead if extended National Weather Service data is available). Seven days is too early, and 1 hour or after the event does not allow corrections.SWRCB Order WQ 2022-0057-DWQ §V.D.2

How often must an inactive project be visually inspected by a QSP or trained delegate, at a minimum?

• a.Weekly, throughout the inactive period
• b.When work resumes after the winter shutdown ends
• c.Monthly, and before a forecast 0.5-inch rain event✓
• d.Once a year, in September before the wet season starts

An inactive project is inspected at least monthly and before a forecast event of that size. A yearly inspection, an inspection at resumption only, or a fixed weekly rule are not in the order.SWRCB Order WQ 2022-0057-DWQ §III.G.2

What is the State specification's definition of an inactive area?

• a.An area smaller than one acre in total size
• b.An area that has no equipment parked on it today
• c.An area located outside the project right of way
• d.An area where no soil-disturbing work has occurred within 15 days✓

An inactive area is one where soil-disturbing work has not occurred within 15 days. Size under one acre, an empty equipment lot and a location outside the right of way do not define an inactive area; the test is 15 days without soil-disturbing work.Caltrans 2024 Standard Specifications §13-1.01B

Saw-cutting slurry reaches a storm drain on Monday at 2:00 p.m. By when must the report required by the State specification be submitted for a non-stormwater discharge?

• a.Within 7 days, by the following Monday
• b.Within 24 hours, which is Tuesday at 2:00 p.m.✓
• c.If a regulator asks for a report
• d.Within 24 hours, by Wednesday at 2:00 p.m.

A non-stormwater discharge is reported within 24 hours (the 48-hour period applies to the end of a storm event resulting in a discharge). A 7-day deadline and a report only on request are not the rule, and Wednesday at 2:00 p.m. counts 48 hours rather than 24.Caltrans 2024 Standard Specifications §13-1.01C(1)

Within how long after a concrete washout becomes full must the waste be disposed of?

• a.Within 24 hours of filling
• b.Within 30 days of filling
• c.Within 2 business days of filling✓
• d.It need not be disposed of

Concrete waste is disposed of within 2 business days after the washout becomes full, at a plant licensed to receive it. Thirty days is too long, 24 hours is shorter than stated, and disposal is required.Caltrans 2024 Standard Specifications §13-9.03

When must a concrete washout be covered?

• a.Before and during every storm event✓
• b.At night, when no concrete is placed
• c.It does not need a cover; it must stay open to dry out
• d.After it has become full

A washout must be covered before and during a storm event so rain does not carry washout waste off site. Covering only at night, leaving it open to dry and waiting until it is full all leave it exposed to rain.Caltrans 2024 Standard Specifications §13-9.03

What is the minimum capacity of a portable temporary concrete washout and of a washout bin?

• a.At least 55 gallons (portable unit); at least 5 cubic yards (bin)✓
• b.At least 5 gallons (portable); at least 1 cubic yard (bin)
• c.At least 30 gallons (portable unit); at least 10 cubic yards (bin)
• d.At least 100 gallons (portable); at least 20 cubic yards (bin)

The specification requires a portable washout of at least 55 gallons and a roll-off bin of at least 5 cubic yards. Five gallons with 1 cubic yard is too small, and the pairs of 30 gallons with 10 cubic yards and 100 gallons with 20 cubic yards are not the stated minimums.Caltrans 2024 Standard Specifications §13-9.02

Where do slurries from saw cutting, coring and grinding of concrete or asphalt go?

• a.Into the soil beside the work
• b.Onto the pavement to dry
• c.Into a concrete washout✓
• d.Into the nearest storm drain

The washout collects truck washout, slurries containing concrete or asphalt from saw cutting, coring, grinding and grooving, and mortar-mixing waste. Pavement, drains and soil would carry the alkaline slurry into runoff.Caltrans 2024 Standard Specifications §13-9.03

A lane closure on a 45 mph road has a 12-foot lane shift. What is the minimum merging taper length?

• a.180 feet
• b.135 feet
• c.405 feet
• d.540 feet✓

At 45 mph or more L = WS = 12 × 45 = 540 feet. The 405 figure uses the WS²/60 formula at 45 mph (12 × 2,025 ÷ 60), and 180 and 135 are the 30 mph and 0.25 L figures.California MUTCD 2026 Edition, Tables 6B-3 and 6B-4

A merging taper is needed on a 30 mph street with a 10-foot lane shift. What is the minimum length?

• a.300 feet
• b.90 feet
• c.150 feet✓
• d.180 feet

At 40 mph or less L = WS² ÷ 60 = 10 × 900 ÷ 60 = 150 feet. Using L = WS gives 300, 180 is the figure for a 12-foot shift, and 90 is half of that.California MUTCD 2026 Edition, Table 6B-4

The calculated length L for a merging taper is 180 feet. What is the approximate minimum shoulder taper length?

• a.About 60 feet✓
• b.About 90 feet
• c.About 100 feet
• d.About 180 feet

A shoulder taper is at least 0.33 L, which is about 60 feet. The 90-foot value is the shifting taper (0.5 L), 180 feet is the merging taper, and 100 feet is the maximum for downstream and one-lane two-way tapers.California MUTCD 2026 Edition, Table 6B-3

What length range applies to a one-lane, two-way traffic taper?

• a.10 feet minimum, 20 feet maximum
• b.50 feet minimum and 100 feet maximum✓
• c.A length of at least L, the merging taper figure
• d.200 feet minimum, 500 feet maximum

The one-lane, two-way traffic taper is 50 feet minimum and 100 feet maximum, as is the downstream taper. The merging taper is at least L, so it is not the one-lane two-way figure, and 10 to 20 feet and 200 to 500 feet are not the ranges stated.California MUTCD 2026 Edition, Table 6B-3

On an urban street with a 40 mph speed limit, within what range should the nearest advance warning sign be placed from the work?

• a.40 to 80 feet
• b.1,500 feet
• c.400 to 800 feet
• d.160 to 320 feet✓

On urban streets the nearest warning sign is placed 4 to 8 times the speed limit in feet, so 4 × 40 = 160 to 8 × 40 = 320 feet. The other ranges use the wrong multiplier or the rural freeway distance.California MUTCD 2026 Edition §6B.04

What is required for flaggers controlling a one-lane, two-way operation?

• a.A whistle, with hand signals as backup
• b.A STOP/SLOW paddle, an emergency-only flag or an AFAD✓
• c.Hand signals alone, which are accepted as quicker
• d.A flashlight, used the same way in daylight

Flaggers use a STOP/SLOW paddle, a flag only for emergencies, or an AFAD, and hand movements alone are prohibited in a one-lane two-way operation except for emergency responders or uniformed officers. Hand signals alone, a whistle and a daylight flashlight are not the specified methods in this operation.California MUTCD 2026 Edition §6D.05

Which marking is required on traffic cones used during the hours of darkness?

• a.A yellow flasher on top of the cone
• b.A retroreflective sleeve✓
• c.A flashing red lamp on every cone
• d.Yellow paint

A traffic cone must have a retroreflective cone sleeve during hours of darkness, and the sleeve type must be the same on all cones in the project. A yellow flasher and a red lamp are lights the rule does not call for, yellow paint does not reflect headlights, and cones are not exempt at night.Caltrans 2024 Standard Specifications §12-3.02B

How must the stripes on a barricade rail slope?

• a.Downward toward the work space, pointing traffic at it
• b.Horizontally across the rail, in alternating bands
• c.Upward in the direction road users are to pass
• d.Downward in the direction that road users are to pass✓

Barricades are placed so the stripes slope downward in the direction road users are to pass, with alternating orange and white retroreflective stripes. Stripes sloping toward the work space point traffic into it, horizontal stripes give no direction, and stripes sloping upward in the direction of passage point to the wrong side.Caltrans 2024 Standard Specifications §12-3.10C

A longitudinal buffer space is to be sized using the manual's stopping sight distance table on a level road with a 50 mph speed. About how long is it?

• a.425 feet✓
• b.200 feet
• c.1,000 feet
• d.570 feet

The stopping sight distance table gives 425 feet at 50 mph on level roads, used as the suggested longitudinal buffer length or flagger station location. The 200-foot value is the 30 mph figure, 570 feet is the 60 mph figure, and 1,000 feet is a freeway sign spacing.California MUTCD 2026 Edition, Table 6B-2

Which topics must flagger training cover before a worker is assigned as a flagger?

• a.Signals, work-zone layout, one-way control✓
• b.Trench shield assembly and shoring installation
• c.Estimating asphalt tonnage and preparing bid prices
• d.Operating a hot mix paver, screed controls and rollers

Flagger training covers flagger equipment, layout of the work zone and station, signaling methods, one-way traffic control, a trainee demonstration, emergency vehicles, emergencies, hostile drivers and single-flagger procedures, with documentation kept. Paver operation, estimating and shield assembly belong to other jobs.8 CCR §1599(g)