Free CHST practice test, sorted by blueprint domain

A carpenter fastens a temporary 2×4 handrail tight against a stairwell wall so there is no gap for a hand. What does 29 CFR 1926.1052(c) require?

Pick the option you would mark on test day. The choice stays fixed, and every option then explains itself.

1. A rail height of 42 in instead of a gap

   42 inches is the guardrail top-rail height; changing height does nothing about the missing hand clearance.
2. A rail flush against the wall

   A rail tight to the wall cannot be gripped at all, which defeats the purpose of a handrail.
3. At least 1 in of clearance behind the rail

   One inch is too tight for fingers to close around the rail; the stairway rule for temporary handrails sets 3 inches.
4. At least 3 in of clearance behind the rail

   A temporary handrail needs at least 3 inches between rail and wall so a hand can wrap around it and hold on.

Workers handling a solvent whose exposure limit carries a 'Skin' notation wear cotton gloves that become soaked. Air sampling shows exposure below the PEL. What is the MAIN concern?

1. Skin absorption that air monitors miss

   A 'Skin' notation flags a chemical that passes through skin in meaningful amounts, and soaked cotton gloves hold it against the hands; skin absorption is a dose that air monitors miss entirely.
2. Eye irritation from the solvent vapor

   Vapor levels are already under the PEL, and eye irritation is not what a skin notation warns about.
3. Ingestion from eating in the work area

   Nothing in the scenario mentions eating at the work area; the soaked gloves point to direct skin contact as the uncontrolled route.
4. Risk is controlled below the PEL

   The PEL addresses inhalation only, so being below it says nothing about solvent absorbed through wet gloves; the risk is not controlled.

A testing contractor will X-ray pipe welds on site with a gamma source and posts a restricted boundary. What must other trades do during the shots?

1. Work inside it 6 ft from the source

   Gamma rays from an industrial source travel far past 6 ft; the boundary distance is set from measured dose rates and is usually much larger.
2. Remain inside it with lead aprons on

   Lead aprons made for medical X-ray do little against the high-energy gamma rays of an industrial radiography source.
3. Enter it if they wear dosimeter badges

   A dosimeter records dose without reducing it, and other trades are not trained or authorized to work inside the radiographer's boundary.
4. Stay outside it until the area is cleared

   The posted boundary marks where dose rates exceed the limit for people who are not radiation workers, so everyone else stays outside it until the radiographer finishes and the area is cleared.

The anti-two-block device on a telescopic boom crane stops working on Monday morning, and parts are on hand. What does 29 CFR 1926.1416(d) require?

1. Use the listed alternative; repair within 7 days

   The anti-two-block device is a Category I operational aid, so the crane may keep working only with the temporary measures the standard lists, and with parts on hand the repair is due within 7 calendar days.
2. Stop lifting until the device is repaired

   Stopping lifting is not what the standard requires: it lets the crane keep working once its listed temporary measures, such as a marked cable and a spotter, are in place.
3. Use the listed alternative; repair within 30 days

   Thirty days is the deadline for Category II aids such as load indicators; the anti-two-block device is Category I, so the listed alternative buys only 7 days.
4. Keep lifting and fix it at the annual inspection

   Waiting for the annual inspection leaves the crane without two-block protection for months; the standard sets a repair deadline measured in days.

A boom lift will be used on a sloped driveway. What does 29 CFR 1926.453(b)(2) require before the platform is raised?

1. Set brakes, pad outriggers, chock wheels

   Before the platform goes up the aerial lift rule calls for set brakes, outriggers on pads or a solid surface, and wheel chocks when the lift stands on an incline and chocks can be placed safely.
2. Set brakes, pad outriggers, skip chocks

   Skipping chocks leaves a lift that can creep on the slope even with brakes set and outriggers padded; chocks are required on an incline.
3. Park across the slope instead of chocking

   Parking across the slope instead of chocking does not remove the chock requirement and adds side-tipping risk when the boom swings.
4. Raise the boom first, then set brakes

   Raising the boom shifts the center of gravity, so the unit is secured before elevation, never after.

Overnight freezing rain coats the walkways between the parking area and the site trailers. What should the site do FIRST, before the shift arrives?

1. Issue boot traction cleats at the gate

   Cleats are PPE, the last line of defense, and they leave the ice in place for anyone without them.
2. Remove the ice and apply sand or deicer

   Clearing the ice and treating the walkways removes the hazard itself, the top of the hierarchy, and it can be finished before anyone walks there.
3. Coach workers to take short, flat steps

   Walking technique is an administrative measure that depends on every worker remembering it on every step.
4. Post slippery-walkway signs at the gate

   Posting warning signs leaves the ice where it is and relies on people changing how they walk.

A contractor will demolish a fire-damaged two-story masonry building. Before any demolition starts, what does 29 CFR 1926.850(a) require?

1. An EPA asbestos clearance for the structure

   Asbestos inspection falls under separate EPA and OSHA asbestos rules, and the demolition paragraph names no EPA clearance.
2. An engineering survey by a competent person

   Before demolition starts, a competent person must survey the structure's condition, including the chance of unplanned collapse, which fire damage makes even more pressing.
3. Notice to OSHA 10 days before demolition starts

   The 10-working-day demolition notice comes from EPA's asbestos NESHAP and goes to EPA or the state agency, not to OSHA.
4. A PE-stamped demolition plan for the building

   The demolition rule asks for a survey by a competent person, not a plan sealed by a professional engineer.

Painters will spray a flammable lacquer inside an enclosed room, and a combustible-gas meter will be used to verify the ventilation. Under NFPA 33, the NFPA standard for spray application, ventilation must keep vapor concentrations below what level?

1. 25% of the UEL

   The upper explosive limit is the wrong end of the flammable range; 25 percent of the UEL can already sit inside the explosive range.
2. 50% of the UEL

   50 percent of the UEL, the upper explosive limit, usually lies inside the flammable range, so it gives no margin against ignition.
3. 25% of the LEL

   NFPA 33 sizes spray-area ventilation to keep flammable vapor below 25 percent of the lower flammable (explosive) limit, the LEL, leaving a margin for richer pockets near the gun.
4. 10% of the LEL

   10 percent of the LEL is the confined space threshold for a hazardous atmosphere, a different rule from spray-area ventilation.

A crew will core-drill and saw-cut a slab in an occupied building where conduits may be embedded. What does 29 CFR 1926.416(a)(3) require before the work begins?

1. Rely on the original plans for conduit

   Original plans often miss later changes, which is why the rule calls for inquiry, observation or instruments rather than relying on drawings.
2. Find out if live circuits run in the slab

   Before work begins the electrical rule requires the employer to determine, by inquiry, observation or instruments, whether energized circuits sit where the work could contact them.
3. Wear rubber gloves and keep cutting

   Gloves do not replace locating the circuits, and ordinary rubber gloves are not rated electrical protection for keeping on cutting.
4. Cut first and stop if sparks appear

   Sparks mean the blade has already hit a live conductor; the check has to come before cutting, not from it.

Workers clear a 1.5-cubic-yard concrete mixer's loading skip by hand with shovels while it is raised. What does 29 CFR 1926.702(b) require?

1. Long-handled shovels for hand clearing

   Longer handles still put workers under or beside the raised skip; the standard calls for a mechanical device in place of hand clearing.
2. A warning horn before the skip rises

   A horn warns before the skip moves but does nothing for people clearing material by hand beneath it.
3. A mechanical device to clear the skip

   Mixers with loading skips of one cubic yard or more must have a mechanical device to clear the skip, plus guardrails on each side, so no one works under or in a raised skip.
4. A spotter watching the skip

   A spotter can watch, but the worker is still in the path of a skip that drops or shifts; the rule removes hand clearing altogether.

Bricklayers repointing mortar want their frame-scaffold platform, 20 feet up, set 16 inches from the wall to give them room. What does 29 CFR 1926.451 require?

1. Move it to within 3 in of the wall face

   Three inches is the limit for outrigger scaffolds, not for a frame scaffold working against a wall.
2. No change if a toeboard is added on that side

   A toeboard stops falling tools and materials but does not keep a worker from stepping into the gap at the inner edge.
3. No change; up to 18 in is permitted

   No change is permitted for this work: the 18-inch allowance covers only plastering and lathing, and repointing mortar falls under the 14-inch limit.
4. Move it within 14 in or guard the inner edge

   A platform's front edge may sit no more than 14 inches from the face of the work unless guardrails or personal fall arrest protect that inner edge, so 16 inches needs one or the other.

A shackle breaks during a lift, dropping the load. How should the broken pieces be handled for the investigation?

1. Tag, bag, and keep them unaltered for analysis

   The fracture faces carry the evidence of overload, fatigue or a material defect, so the pieces are tagged, bagged and kept unaltered for a lab or metallurgist.
2. Photograph them, then discard the broken parts

   Photographs alone cannot replace the parts, and discarding them destroys the physical evidence a lab needs to examine.
3. Clean the fracture faces before photos

   Cleaning the fracture faces strips corrosion, paint and deposits that help show how long a crack had been growing before the break.
4. Fit the broken pieces back together

   Fitting the broken pieces back together crushes the fine features an analyst reads on the fracture.

An electrician receives a 277-volt shock from a mislabeled circuit. He says he feels fine and wants to get back to work. What should the supervisor do?

1. Treat it as first aid and let him continue

   Calling it first aid skips the medical check and assumes there is no injury before anyone qualified has looked.
2. Watch him for an hour, then decide

   A supervisor cannot detect a heart rhythm problem by watching, and waiting only delays the evaluation.
3. Let him work if no burns can be seen

   Electrical injury is often internal, so the lack of visible burns does not show the shock was harmless.
4. Send him for medical care now

   Current can injure the heart and deep tissue without visible burns, and rhythm problems may not show at once, so a significant shock means prompt medical care and evaluation.

A worker fell from a ladder set on mud. He had taken a sedating cold medicine that morning, which made him less alert but did not by itself cause the fall. How should the medicine's effect be classified?

1. An unrelated factor

   The medicine made the worker less alert, so it is tied to the event and is not an unrelated factor.
2. The root cause

   A root cause is the underlying system failure that, once fixed, prevents recurrence, such as having no fitness-for-duty check; the drowsiness alone is not that.
3. A contributing factor

   The drowsiness from the medicine made the fall more likely without causing it on its own, which is exactly what a contributing factor is.
4. The immediate cause

   The immediate cause is the condition at the moment of the fall, here the ladder set on mud.

One floor of an occupied building is being gutted. On day one the crew wants to remove the fire doors and rated walls that separate the work area from the occupied floors. Under 29 CFR 1926.150(f), what applies?

1. Keep them in place during night shifts

   The rule has no shift-based schedule; the cutoffs stay in place day and night until the work itself requires removing them.
2. Keep them until the work requires removal

   In buildings under alteration or demolition, fire cutoffs stay in place until the operations make removal necessary, so they cannot all come out on day one.
3. Remove them if extinguishers are added

   Extinguishers do not stop fire and smoke from spreading the way rated doors and walls do, so adding them cannot substitute for the cutoffs.
4. Remove them once occupants are warned

   A warning does not protect people on occupied floors from a fire that starts in the work area.

A release on site of an extremely hazardous substance exceeds its reportable quantity and could affect the neighborhood. Besides the National Response Center, whom does EPCRA Section 304 require the contractor to notify immediately?

1. The city building department and police

   Police may answer a 911 call, but EPCRA names the state and local emergency planning bodies, not the building department or police, as the required recipients.
2. The project's insurance carrier

   Telling the insurance carrier is a business step and satisfies no federal release-reporting duty.
3. State and local emergency planners

   EPCRA Section 304 requires immediate notice of a reportable release of an extremely hazardous substance to the State Emergency Response Commission and the Local Emergency Planning Committee for each area likely to be affected, with a written follow-up.
4. OSHA's area office within 8 hours

   OSHA's 8-hour clock is for reporting a work-related fatality; it has nothing to do with a chemical release reaching the community.

Miners in a tunnel could be trapped by smoke or gas from a fire at the shaft. What does 29 CFR 1926.800 require for these workers?

1. Self-rescuers at the work stations

   Approved self-rescuers must be immediately available at underground work stations, so each worker can put one on within seconds if smoke or gas cuts off the way out.
2. Escape hoods stored at the surface

   Equipment kept at the surface cannot help workers who are cut off underground; it has to be where they work.
3. An SCBA carried by the foreman

   An SCBA carried by the foreman leaves the rest of the crew unprotected; every exposed worker needs a device within reach.
4. Dust masks issued to each worker

   Dust masks filter particles but supply no oxygen and give no protection against carbon monoxide or fire gases.

During an inspection, an OSHA compliance officer finds an imminent danger in a deep unshored trench, and the contractor refuses to pull its workers out. What can OSHA do to stop the work?

1. Ask local police to arrest the foreman

   Local police do not enforce federal OSHA standards, and OSHA itself has no arrest power.
2. Seek a federal district court order

   The OSH Act gives OSHA no power to close a site on its own; for an imminent danger it asks a U.S. district court for an order restraining the work.
3. Padlock the site on the officer's authority

   Compliance officers have no authority to padlock or close a workplace; only a court can order the work stopped.
4. Issue an on-the-spot fine and leave

   There is no on-the-spot fine: citations and penalties come later from the Area Office, and leaving does nothing for workers still in the unshored trench.

A small contractor is thinking about asking OSHA's On-Site Consultation Program for a free hazard assessment of its yard. Which statement about the program is correct?

1. It begins after an OSHA citation

   Employers request a visit voluntarily, usually with no inspection in sight; it does not begin after an OSHA citation as a follow-up.
2. Serious hazards found need not be fixed

   Employers who use the service agree to correct the serious hazards the consultant identifies within an agreed time.
3. It is separate from enforcement

   On-Site Consultation is a free, confidential service separate from OSHA enforcement; consultants issue no citations or penalties.
4. Findings go to OSHA enforcement

   Consultation results stay with the employer and are not passed to enforcement inspectors, which is what makes the service safe to request.

At the end of each project, a GC wants its subcontractors' safety performance on that job to influence future bids. What practice BEST does this?

1. Rate each sub at closeout for prequal

   Scoring each subcontractor's safety performance at closeout and feeding the score into prequalification ties what happened on this job to future award decisions.
2. Use each sub's next EMR letter

   The EMR letter is a delayed, company-wide figure driven by insurance claims, so it says little about how a sub performed on this particular job.
3. Ask subs to rate themselves

   Asking subs to rate themselves produces scores that are neither independent nor verifiable and tend to be favorable; the GC's own observations should count.
4. File the safety logs in project archives

   Filing the safety logs in archives keeps records but links nothing to future bidding, which is the point of the GC's request.

A carpenter sprains an ankle playing in an after-hours company softball game that is voluntary and held at a city park. He needs prescription medication. Is the case work-related for OSHA recordkeeping?

1. Yes; the company sponsored the game

   Sponsorship alone does not make a game part of work; what decides the case is that playing was voluntary.
2. No; recreational activity is excluded

   An injury that results solely from voluntary participation in a recreational or fitness activity is excluded from work-relatedness, so the case is not recorded even with a prescription.
3. No; a prescription counts as first aid

   A prescription is medical treatment beyond first aid and would make a work-related case recordable; this case is not recorded because it fails work-relatedness.
4. Yes; prescription drugs make it recordable

   Prescription medication is a recording criterion only once a case is work-related, and this one fails that first test.

A carpenter injured on December 20 is still off work when the 300A summary is prepared in January. How should the days away be recorded?

1. Last year's log, with an estimate

   The case stays on the log for the year of the injury, and if the worker is still off when the summary is prepared, the employer estimates the total days away and updates the entry later.
2. Hold the 300A until he returns to work

   The 300A cannot be held for one worker: it is certified and posted from February 1 to April 30 on schedule, using an estimate.
3. The new year's log, once he returns

   Moving the case to the new year would misstate both years' records; the injury date fixes which log it goes on.
4. Split across both years' logs

   Days away are not divided between logs; the whole case belongs to the year in which the injury happened.

A site's inspection program grades findings A, B or C by potential severity. An inspector finds a scissor lift in use on an upper deck with its tilt alarm and pothole guards bypassed and rates it Class A. How should it be handled?

1. Fix it within the weekly correction cycle

   A weekly cycle suits lower-severity items; a lift in use with its tip-over protection bypassed cannot wait days.
2. Add it to the next monthly audit

   Deferring a Class A hazard to the next audit leaves people exposed for weeks.
3. Log it for the safety committee to rank

   The severity has already been rated; routing it to a committee adds delay and no protection.
4. Control the exposure immediately

   A Class A finding could cause death or serious injury, so the exposure is controlled at once, by taking the lift out of service, before the permanent repair is scheduled.

Two similar contractors each had $100,000 in workers' comp losses over the rating period. Contractor A had one $100,000 claim; Contractor B had twenty claims of $5,000 each. Whose EMR will likely be hurt more?

1. Neither; EMR excludes medical claims

   Medical claims enter the EMR alongside lost-time cases, so the idea that EMR excludes them is wrong.
2. B's; frequency drives the EMR more

   The EMR formula counts the first part of every claim at full weight and discounts the excess of large claims, so many small claims raise the modifier more than one big claim of the same total.
3. A's; one large claim weighs the most

   Above the split point a large claim is discounted, so the single $100,000 loss weighs less than twenty small ones.
4. Neither; equal losses, equal EMRs

   Equal dollar totals do not give equal modifiers because the formula separates primary and excess losses.

A contractor is starting a peer-observation behavior-based safety process. Which practice MOST protects workers' trust in it?

1. Supervisors carry out the observations

   A peer process relies on coworkers observing each other; having supervisors carry out the observations makes them feel like inspections and erodes trust.
2. Results are posted by crew each week

   Posting results crew by crew each week invites ranking and blame, which pushes crews to hide at-risk behavior instead of discussing it.
3. Observers record names for targeted retraining

   Recording names turns peer observation into surveillance, so workers act differently when watched and observers soften what they record.
4. Data are anonymous and not used for discipline

   Peer observation works only when workers trust that what an observer writes down will not be used against them, so the data are anonymous and kept out of the discipline process.

A contractor wants to replace classroom respirator instruction with a self-paced online module, with no live person available to answer questions. Under OSHA's interpretations on online courses, what is missing?

1. Nothing, if workers pass the module's final quiz

   A passing quiz score shows recall, not that a worker can put on and check a respirator, and it still leaves no one to answer questions.
2. A rule to repeat the module every six months

   Respirator training is already required yearly, and repeating a flawed module more often adds neither a trainer nor practice.
3. A qualified trainer and hands-on practice

   OSHA accepts computer-based training only when workers can put questions to a qualified trainer and, for respirators, practice donning and seal checks with the actual equipment.
4. A certificate signed by each worker

   A signed certificate documents completion; it does not supply the missing interaction or the hands-on practice.

A contractor has detailed procedures, regular audits and plenty of statistics, but safety is driven by management, treated as compliance with rules, and workers rarely propose improvements. On the Hudson safety culture ladder, which level is this?

1. Generative

   In a generative culture safety is part of how everyone works and workers keep looking for improvements, the opposite of what is described.
2. Pathological

   A pathological culture cares about safety only to avoid being caught, so it would not keep detailed procedures and regular audits.
3. Calculative

   At the calculative rung the organization has systems, audits and plenty of data, but safety is imposed by management and treated as compliance, with little input from the workforce.
4. Proactive

   At the proactive rung the workforce starts to take the initiative and values drive safety, which this contractor has not yet reached.

A subcontractor's HazCom training covers only label elements and pictograms. Under 1910.1200(h)(3), which required training element is missing?

1. Methods to detect a release of the chemicals

   HazCom training must cover the methods and observations workers can use to detect the presence or release of a hazardous chemical, such as monitoring, odor or visible signs, along with the hazards, protective measures and program details.
2. The supplier's trade-secret formulation data

   Trade-secret formulation data can be withheld from the SDS under set conditions and is not part of required worker training.
3. Purchase and inventory records for each product

   Purchase and inventory records support the chemical inventory the employer keeps, but workers do not need them in training to handle the products safely.
4. The OSHA penalty schedule for HazCom

   The OSHA penalty schedule concerns the employer's liability and gives workers nothing they need to protect themselves; the training rule does not list it.

On its last highway project, a contractor had three struck-by incidents during night paving, all tied to poor lighting and shifting work zones. It is now bidding a similar night project. What is the BEST use of those lessons?

1. Watch whether the same problems recur first

   Waiting for the same incidents to happen again ignores evidence the contractor already holds.
2. Reuse the prior project's traffic plan unchanged

   The old traffic plan is part of what failed, so reusing it repeats the conditions behind the three incidents.
3. File the old investigation reports for reference

   Filing the old investigation reports keeps the knowledge on a shelf where it never reaches the new project's planners or crews.
4. Build the findings into the new project plan

   Lessons learned pay off only when they change the next job, so lighting, traffic control and work-zone layout are designed into the new plan and bid from the start.

Crews shrug off the risk of the grinding they do every day but worry intensely about a rare crane collapse. Which risk-perception factor BEST explains their low concern about grinding?

1. Involuntary exposure to the hazard

   Involuntary exposure makes a risk feel larger, and the crews choose and control their own grinding.
2. Familiarity and a sense of control

   Hazards people face every day and feel in control of seem smaller than they are, so routine grinding draws little concern despite constant exposure.
3. Low probability of being exposed

   The crews grind daily, so exposure is near certain and cannot explain their low concern.
4. High dread of the possible outcome

   Dread raises perceived risk; it explains the fear of the crane collapse, not the calm about grinding.