CHST Practice Questions (2026) — Free Sample Questions with Answers

Answer: B

Have her wear the loose harness with the straps cinched as tightly as possible: A harness that does not fit after adjustment can let the worker slip out or cause injury during arrest.

Obtain a harness in a size that properly fits her before she works at height: Correct. 29 CFR 1926.95(c) requires PPE to be selected so it properly fits each affected employee.

Issue her a body belt, which is easier to adjust for small frames: Body belts are not permitted as part of a personal fall arrest system.

Assign a coworker to watch her whenever she is tied off: Observation does not fix a poorly fitting harness.

Construction PPE must be of safe design for the work and selected to properly fit each affected employee (1926.95(c)).

Answer: A

1. Formula: Fe = Σ (T ÷ L), with L from Table D-2.
2. Breaker: T = 2 h at 100 dBA, L = 2 h → 2 ÷ 2 = 1.00.
3. Saw-cutting: T = 3 h at 95 dBA, L = 4 h → 3 ÷ 4 = 0.75.
4. Loading: 85 dBA is below the lowest Table D-2 level (90 dBA). By the usual convention for 1926.52, periods below 90 dBA are not counted, so this period adds no term.
5. Fe = 1.00 + 0.75 = 1.75. Because Fe exceeds 1, the exposure exceeds the 1926.52 permissible level; feasible engineering or administrative controls come first, with hearing protection if they do not reduce exposure enough.

1.75: Correct. Fe = 2/2 + 3/4 = 1.00 + 0.75 = 1.75. Table D-2 starts at 90 dBA, and by the usual convention for 1926.52 the 85-dBA period is not counted. Fe > 1, so the exposure exceeds the permissible level.

1.94: Adds 3/16 for the 85-dBA period by extrapolating a 16-h duration, a general-industry (1910.95 Table G-16a) habit; Table D-2 starts at 90 dBA, so construction calculations do not count that period.

2.33: Inverts the 95-dBA ratio (L/T = 4/3 instead of T/L = 3/4).

3.50: Shifts one step on the table (95 dBA read as 2 h, 100 dBA as 1 h).

In construction, sum T/L for each period using Table D-2 (90 dBA for 8 h, 5-dB halving); by convention, periods below 90 dBA (the lowest table level) are not counted. Fe above 1 means the permissible exposure is exceeded.

Answer: B

1. Formula: T = (W/n) ÷ sin θ, with θ measured from the horizontal.
2. Share per leg: W/n = 7,000 lb ÷ 2 = 3,500 lb.
3. Angle factor: sin 60° = 0.866 (as given).
4. T = 3,500 lb ÷ 0.866 = 4,041.6 lb, which rounds to 4,042 lb per leg.
5. Check: the answer is above 3,500 lb, as it must be for any leg angle under 90°; each sling and hardware component must be rated for at least 4,042 lb.

3,031 lb: Multiplies the per-leg share by sin θ (3,500 × 0.866) instead of dividing by it.

4,042 lb: Correct. T = (7,000 lb ÷ 2) ÷ 0.866 = 4,041.6, or 4,042 lb per leg, more than the 3,500-lb share because the legs are not vertical.

7,000 lb: Divides by cos 60° (0.500), treating the angle as if it were measured from the vertical.

8,083 lb: Does not split the load between the two legs (7,000 ÷ 0.866).

Sling leg tension increases as the angle from horizontal decreases; divide each leg's share of the load by the sine of the horizontal angle.

Answer: D

1. Formula: clearance = AD + HS + SM.
2. Substitute: 3.5 ft + 1 ft + 2 ft.
3. Sum: 6.5 ft.
4. Check: the worker's feet drop by the same distance as the D-ring, so measuring from the working surface needs no D-ring-height term; 6.5 ft is more than any partial sum.

3.5 ft: Uses only the SRL arrest distance and leaves out harness stretch and the safety margin.

4.5 ft: Drops the 2-ft safety margin.

5.5 ft: Skips the 1-ft harness stretch and D-ring shift.

6.5 ft: Correct. 3.5 + 1 + 2 = 6.5 ft of clear space is needed below the working surface.

With an SRL anchored overhead, clearance below the working surface is the manufacturer's arrest distance plus harness stretch and D-ring shift plus a safety margin; any swing or anchorage offset adds more.

Answer: B

1. Rule (1926.1053(b)(5)(i)): horizontal distance from the top support to the foot ≈ 1/4 of the working length.
2. Working length = distance along the ladder from the foot to the top support = 20 ft (the 3-ft extension is above the support and not counted).
3. Base distance = 20 ft ÷ 4 = 5.00 ft.
4. Check: 5 ft out for about 19.4 ft of rise gives the intended angle of about 75.5°.

4.25 ft: Subtracts the 3-ft extension from the working length (17 ft ÷ 4).

5.00 ft: Correct. 1926.1053(b)(5)(i): the base is about one-quarter of the working length out, 20 ft ÷ 4 = 5.00 ft.

5.75 ft: Adds the 3-ft extension above the eave to the working length (23 ft ÷ 4).

6.00 ft: Uses the full 24-ft ladder length rather than the working length to the top support.

Set a non-self-supporting ladder at 1:4, using the working length to the top support, not the overall ladder length.

Answer: B

1. Formula: C = 10 ft + 0.4 in × (kV − 50).
2. Voltage above 50 kV: 138 kV − 50 kV = 88 kV.
3. Added distance: 0.4 in × 88 = 35.2 in; 35.2 in ÷ 12 in/ft = 2.93 ft.
4. C = 10 ft + 2.93 ft = 12.9 ft. Check: the answer exceeds the 10-ft minimum, as it must for a line over 50 kV.

10.0 ft: Uses the 10-ft clearance for lines of 50 kV or less and skips the added distance for higher voltage.

12.9 ft: Correct. 0.4 in × (138 − 50) = 35.2 in = 2.93 ft; 10 ft + 2.93 ft = 12.9 ft.

14.6 ft: Multiplies 0.4 in by the full 138 kV instead of only the kV above 50.

20.0 ft: Applies the 20-ft crane clearance from 1926.1408 to a scaffold.

Scaffold clearance from uninsulated lines is 10 ft up to 50 kV, plus 0.4 in for each kV above 50 kV.

Answer: C

Location 1: All readings are normal: 20.9% oxygen and low flammable gas.

Location 2: Applies the 10% LFL confined-space criterion of Subpart AA; the excavation rule is 20% LFL, so 12% does not exceed it.

Location 3: Correct. 19.1% oxygen is below the 19.5% oxygen-deficiency limit in 1926.651(g)(1)(i), so ventilation or other control must continue before entry.

Location 4: CO at 31 ppm is below the 35 ppm setpoint; it warrants watching, not a closed area.

Excavation atmospheres: oxygen below 19.5% is oxygen-deficient, and flammable gas must be kept at or below 20% of the LFL; keep testing as often as needed.

Answer: B

1. Formula: N = A ÷ 3,000 sq ft, rounding up when the remainder is a major fraction (more than half).
2. Substitute: N = 14,000 sq ft ÷ 3,000 sq ft = 4.67.
3. The remainder 0.67 is a major fraction, so round up: N = 5.
4. Check: 5 × 3,000 = 15,000 sq ft ≥ 14,000 sq ft, and the one-per-floor rule is met. Answer: 5.

4: Truncated 4.67 to 4; the 0.67 remainder is a major fraction and needs its own extinguisher.

5: Correct. 14,000 ÷ 3,000 = 4.67; the 0.67 remainder is a major fraction, so 5 extinguishers rated 2A are required.

6: Added a separate extinguisher for the "one per floor" rule; the area-based units already satisfy it on a one-story building.

7: Treated the "2A" rating as 2,000 sq ft of coverage (14,000 ÷ 2,000); the rule is one per 3,000 sq ft.

One 2A extinguisher per 3,000 sq ft or major fraction thereof (plus the 100-ft travel limit and at least one per floor).

Answer: A

No process existed for installing and verifying covers before other trades entered: Correct. The root cause is the management-system gap that let an unsecured, unmarked cover exist and go undetected; fixing it prevents recurrence across crews.

The plywood cover was not secured or marked: Wrong: this is the immediate (direct) condition, which itself resulted from the missing process.

The laborer was not tied off to an anchorage with a personal fall arrest system: Wrong: this is a contributing factor at most and does not explain why the hazard existed.

The laborer did not watch where he was stepping: Wrong: this blames the worker for an unsafe act and stops the analysis too early.

Root causes are system failures behind the unsafe act or condition; fixing them prevents the whole class of incidents.

Answer: C

1. Formula: DART = (N × 200,000) ÷ H.
2. Classify: case 1 is recordable (sutures) but not DART; cases 4 and 6 are first aid only; cases 2 (days away), 3 and 5 (restricted) are DART cases, so N = 3.
3. Substitute: DART = (3 × 200,000) ÷ 160,000 = 600,000 ÷ 160,000.
4. Compute: DART = 3.75.
5. Check: 3.75 × 160,000 ÷ 200,000 = 3 cases. Answer: 3.75.

1.25: Wrong: counts only the days-away case and leaves out the two restricted-work cases.

2.50: Wrong: misses one restricted case; the toe fracture with 5 days of restricted duty is also a DART case.

3.75: Correct. Cases 2, 3 and 5 involve days away or restricted duty: 3 × 200,000 ÷ 160,000 = 3.75.

5.00: Wrong: this is the TRIR — it adds the sutured laceration, which is recordable but not a DART case.

DART counts only recordable cases with days away, restricted work or job transfer; first aid is never counted.

Answer: D

Rely on the general contractor, which as controlling employer is the only citable employer: Wrong: more than one employer can be cited on a multi-employer site; the exposing employer keeps its own duties.

Nothing further, because it did not create the hazard: Wrong: an exposing employer is citable if it fails to protect its own exposed employees, even when another employer created the hazard.

Remove its crew from the project until OSHA inspects the site: Wrong: removing employees from the job is expected only in extreme (imminent danger) situations, not as the routine response.

Inform its employees of the hazard and take reasonable alternative protective measures: Correct. An exposing employer without authority to correct must ask the creating/controlling employer to correct the hazard, inform its employees, and take reasonable alternative measures (e.g., personal fall protection or keeping workers away).

Exposing employer lacking authority: ask for correction, inform employees, take reasonable alternative protection.

Answer: A

Reassess for hazards the water adds, such as slips and shock: Correct. A new control can add hazards: slurry makes floors slippery, and water near an electric saw and its cords calls for GFCI protection and cord management, so the task is reassessed before the change is closed.

Mark the silica hazard eliminated and close the JHA entry: Wet cutting reduces dust; it does not eliminate silica exposure, and the Table 1 conditions still apply.

Remove the task from the written silica exposure control plan: Table 1 tasks stay in the written exposure control plan (1926.1153(g)).

Return the dry saw to the rental yard and close the change: Closing the change without checking for new hazards skips the reassessment step.

Risk reduction is not finished when a control is installed: reassess the task for residual risk and for any new hazards the control introduces.

Answer: A

Ask the maker to confirm the SRL is rated for leading-edge use: Correct. Foot-level anchorage lengthens the free fall and loads the line over a sharp edge; only the manufacturer can confirm the model is rated for that use, or leading-edge-rated SRLs must be used.

Have a competent person inspect each SRL before every use: Pre-use inspection is required, but it cannot show whether this model will survive an edge loading it was not designed for.

Add an energy-absorbing lanyard in series with each of the SRLs: Combining components without the manufacturer's approval can increase fall distance and defeat the SRL's braking.

Proceed, since any ANSI Z359-compliant SRL is strong enough: Ratings apply to the tested use; an overhead-rated SRL can be cut or overloaded when it falls over an edge.

When equipment will be used outside the conditions in its instructions, consult the manufacturer before use; foot-level leading-edge work needs an SRL rated for it.

Answer: A

Competent-person retraining in a language the workers understand, verified hands-on: Correct. Under 29 CFR 1926.503(a)(2) each exposed employee must be trained by a competent person, and OSHA's training policy says training must be presented in a manner employees can understand. A hands-on check confirms they actually understood it.

An English handout of the video's key points for the workers to study at home: This repeats the language barrier that made the first session ineffective.

Signed acknowledgments from each worker stating that the training was received and understood: A signature does not create understanding. These workers have already shown they did not understand the training.

A bilingual coworker who reads the quiz questions aloud during a retest: Translating only the quiz measures nothing new. The workers still never received the content in a form they understand.

Training only counts if workers understand it: deliver it in their language and vocabulary and verify comprehension, as 1926.503(a) requires a competent person to train each exposed employee.