Hierarchy of Controls Explained (With Real Examples)

What Is the Hierarchy of Controls?

The hierarchy of controls is a system for managing workplace hazards, ranked from the most effective method down to the least. It is not a suggestion. It is the framework mandated under WHS Regulations across Australia, as Builder Assist and SafeWork NSW both confirm in their official guidance.

The idea is simple. Before you hand someone a pair of safety glasses and call it a day, you should first ask whether you can get rid of the hazard entirely. If you cannot eliminate it, can you replace it with something less dangerous? Can you put a physical barrier between the worker and the hazard?

PPE, the thing most people jump to first, is actually the last resort.

How Many Levels?

The Australian model recognises six levels: elimination, substitution, isolation, engineering controls, administrative controls, and PPE. Some sources combine isolation and engineering controls into a single tier, giving you five levels. Both approaches are valid, but the six-level version is what appears in SafeWork NSW's official hierarchy document and the model WHS Code of Practice.

The 6 Levels

Each level down means less reliability and more dependence on human behaviour. As Control Hire puts it, "higher order controls are always preferred as they provide more reliable protection."

Level 1: Elimination

Remove the hazard completely. If the hazard does not exist, nobody can be harmed by it. This is the gold standard.

Real examples:

• Prefabricating components at ground level instead of assembling them at height. Workers spend minutes at height instead of hours.
• Designing out confined space entry by installing external access points for maintenance
• Removing asbestos before renovation rather than working around it
• Using pre-cut materials ordered to spec instead of cutting on site. No cutting means no silica dust and no noise.

Elimination is not always possible. But it should always be the first question you ask.

Level 2: Substitution

Replace the hazard with something less dangerous. The work still gets done, but with a lower risk profile.

Real examples:

• Battery-powered tools instead of 240V corded tools in wet areas. Battery voltage cannot deliver a lethal shock.
• Water-based coatings instead of solvent-based where possible. Lower toxicity, less flammable, no respiratory protection required.
• Telehandler instead of manual handling for heavy materials
• Pre-mixed concrete instead of mixing on site to avoid cement dust exposure

Substitution does not eliminate the risk entirely. It reduces it. A battery tool can still cause injuries. But the worst-case outcome is dramatically less severe.

Level 3: Isolation

Physically separate the hazard from people. This is where the Australian six-level model differs from the five-level version used in some other countries.

Real examples:

• Barricading an open excavation so workers cannot fall in
• Enclosing a noisy compressor in a sound-rated housing
• Lockout/tagout systems that physically prevent equipment from being re-energised while someone is working on it
• Exclusion zones around mobile plant that keep pedestrians clear

Level 4: Engineering Controls

Build safety into the work environment. Engineering controls put a barrier, guard, or system between the person and the danger without relying on people remembering to do something.

Master Builders QLD provides construction-specific examples of engineering controls in their guidance material. Common applications include:

• Edge protection and guardrails on scaffolding and elevated platforms
• Machine guarding on grinders and saws that prevents contact with the blade
• Local exhaust ventilation (LEV) that captures dust at the source
• Trench shoring and benching that prevents collapse

Engineering controls require upfront investment, but they pay off because they work passively. A guardrail does not take a break.

Level 5: Administrative Controls

Change the way work is organised. Administrative controls do not remove the hazard. They manage exposure through rules, procedures, training, and scheduling.

These are less reliable because they depend on people following instructions consistently.

Real examples:

• Job rotation to limit exposure time to a hazard
• Scheduling noisy work before or after other trades are in the area
• Permit-to-work systems for high-risk activities
• Speed limits and traffic management plans on site
• Toolbox talks that communicate hazards and procedures
• Signage and exclusion zones around hazardous work areas

Administrative controls are important, but they should never be the first or only control.

Level 6: PPE (Personal Protective Equipment)

The last line of defence. PPE protects the individual worker when higher-level controls have been applied and residual risk remains.

PPE is the least effective level because it does not reduce the hazard at all. The danger is still there in full force. The PPE just attempts to protect the body from the consequences.

Real examples:

• Safety glasses when using a grinder after the guard is fitted and LEV is in place
• Hearing protection when working near plant that cannot be enclosed
• Hard hats in areas with overhead work after exclusion zones and catch platforms are set up
• Respiratory protection when dust controls are in place but residual exposure remains

PPE only works when it is:

• The correct specification for the hazard
• Properly fitted to the individual
• In serviceable condition and within its use-by date
• Worn consistently and correctly every time

If any of those conditions fail, the protection fails. That is four points of failure for a single control.

Why Skipping Levels Is a Legal Problem

AlertForce makes this point clearly: "skipping straight to PPE without considering elimination or substitution likely breaches your legal duty of care."

Under WHS law, duty holders must work through the hierarchy when deciding how to manage risks. Skipping levels without documented justification is a compliance failure. If an inspector reviews your SWMS and finds PPE listed as the only control for a hazard where higher-level controls were feasible, you have a problem.

If PPE is the only control listed against a hazard in your SWMS or JSA, you have not applied the hierarchy. Go back and work through the higher levels first.

How to Apply This in Your SWMS and JSA

When writing a SWMS or JSA, the hierarchy should be your framework for every single hazard.

The Process

1. Identify the hazard - what could cause harm?
2. Start at the top - can you eliminate the hazard entirely?
3. Work down - if elimination is not feasible, can you substitute? Isolate? Engineer a control?
4. Layer controls - most hazards need controls from multiple levels working together
5. PPE last - specify what is required after all other controls are in place

Layering Is Normal

In practice, most hazards are managed with a combination of controls from multiple levels. Working at heights might involve:

• Elimination of some tasks by prefabricating at ground level
• Isolation through edge protection barriers
• Engineering controls like scaffolding with guardrails
• Administrative controls like a permit system and competency verification
• PPE as the final layer with a harness for specific tasks beyond the guardrail

That is five levels of the hierarchy working together. Each one backs up the others.

Common Mistakes

• Jumping straight to PPE without considering higher-level controls. This is the most common failure in SWMS and JSA documents.
• Listing only one control per hazard when the risk clearly needs multiple layers
• Using vague controls like "take care" or "be aware." These are not controls. A control is a specific, measurable action.
• Not reviewing controls when conditions change. The hierarchy needs to be re-applied whenever the job, environment, or equipment changes.
• Treating the hierarchy as optional. It is not. It is embedded in Australian WHS legislation.

Put It Into Practice

Understanding the hierarchy is one thing. Applying it consistently across every SWMS, JSA, and Take 5 is another. It takes discipline to start at the top every time, especially when PPE is sitting right there in the ute.

Burgy builds the hierarchy of controls directly into the SWMS and JSA creation process. When you are assigning controls to a hazard, the hierarchy framework guides you through each level so nothing gets skipped. Your documents demonstrate proper application of the hierarchy, which is exactly what an auditor or inspector expects to see.