Hierarchy of controls examples for construction sites

The five levels in plain words

1. Eliminate. Remove the hazard so no one is exposed. Do the work somewhere else, or do not do it.
2. Substitute. Swap in something less hazardous.
3. Engineer. Put a physical barrier or system between people and the hazard.
4. Administer. Change procedures, schedules, training and signs.
5. PPE. Protect the individual. It works only if the person wears it correctly every time.

Think of it as how much you depend on people doing the right thing. Eliminate depends on nobody. PPE depends on everybody.

Example 1: working at an unprotected edge

• Eliminate: build the roof components on the ground, so less work happens at height.
• Engineer: guardrail systems at the edge.
• Administer: a written plan and a competent person's inspection, plus training.
• PPE: personal fall arrest, used where a guardrail is not feasible.

The strongest answer is the one that keeps people from reaching the edge at all. Rules for these systems are in 1926 Subpart M, covered in the fall protection guide.

Example 2: silica from cutting masonry

• Eliminate or substitute: use a precast or pre-cut product so cutting on site is unnecessary.
• Engineer: a saw with water delivery or dust collection.
• Administer: work scheduling that keeps other trades out of the area.
• PPE: respirators, selected under the employer's program.

The health hazards guide names the standards for silica, lead and noise by number.

Example 3: noise from a saw or breaker

• Substitute: choose a quieter tool or method.
• Engineer: enclosures and dampening.
• Administer: limit the time any one worker spends in the noise.
• PPE: hearing protection.

Notice that hearing protection is the last step, even though it is the one most sites reach for first.

Example 4: a trench

• Eliminate: use a method that avoids entry, such as trenchless installation or pre-assembled sections.
• Engineer: sloping, benching, shielding or shoring, per Subpart P.
• Administer: a competent person's inspections and a rule that no one enters until cleared.
• PPE: none of it protects against a cave-in, so PPE is not the control here at all.

The trench sloping calculator helps with the engineering step.

Example 5: a toxic chemical

• Substitute: a less hazardous product.
• Engineer: local ventilation.
• Administer: the hazard communication program with labels and safety data sheets, covered by 1926.59 and cross-referenced to general industry.
• PPE: gloves, eye and respiratory protection chosen for that chemical.

The trap that costs the most points

Many candidates choose PPE or training because those answers are familiar and true. The exam asks for the best answer, and when a question asks for the most effective control, higher on the hierarchy wins. Training is administrative. It matters, but it relies on human behavior, so it sits below an engineering control.

There is one exception worth knowing. If a question asks what to do right now with no time to engineer anything, such as protecting a worker already exposed, a lower-level control can be the correct immediate action. Read whether the stem asks about the best long-term control or the immediate step.

How to drill it

Pick any hazard on a site you know. Write one control for each level. If you cannot fill one, that gap is your study target. Then use the CHST flashcards between sessions for the subpart and control terms.

See where you stand

Take the free 10-question check and note which questions ask for the strongest control. It needs no signup and explains every answer.

FAQ

Is PPE ever the best answer on the CHST?

Yes, when the stem says other controls are not feasible, or when it asks for the final layer of protection. Read the stem for that signal.

Where does training fit in the hierarchy?

Training is an administrative control, so it ranks below elimination, substitution and engineering controls.

Is the hierarchy the same in every safety text?

Versions differ slightly in how many levels they show, but the order from elimination down to PPE is consistent. Learn the five-level version above.