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Step 3: Control Risks

Overview​

After identifying and assessing risks, the most important step is implementing controls to eliminate or minimize them. The law requires using the Hierarchy of Control—a systematic ranking of control measures from most effective to least effective.

[!important] Legal Requirement WHS Regulation 36 requires PCBUs to eliminate risks so far as is reasonably practicable. If elimination is not reasonably practicable, risks must be minimized using the hierarchy of control measures.

The hierarchy ensures that:

  • Higher-level controls that physically remove hazards or change the risk at the source are prioritized
  • Lower-level controls that rely on human behavior are used only when higher-level controls are not reasonably practicable
  • Multiple layers of controls provide redundancy if one control fails

The Hierarchy of Control Measures​

Controls are ranked in three levels:

Level 1: Elimination (Most Effective)​

Eliminate the hazard completely.

Remove the hazard entirely from the workplace so the risk no longer exists.

Why Most Effective: If you eliminate the hazard, you eliminate the risk. No other controls are needed, maintenance requirements are eliminated, and workers cannot be exposed.

Construction Examples:

Prefabricate at Ground Level: Assemble roof trusses, wall frames, and structural components on the ground instead of working at heights. The completed assemblies are then lifted into position by crane, eliminating fall risks during assembly.

Eliminate Confined Space Entry: Design tanks and vessels with external inspection ports and remote monitoring systems, removing the need for workers to enter confined spaces.

Eliminate Manual Handling: Use mechanical aids (cranes, forklifts, conveyors, hoists) to move materials instead of manual lifting. For example, using a materials hoist to raise bricks to upper floors eliminates repetitive manual carrying.

Design Out Hazards: Specify materials that do not contain hazardous substances—for example, using pre-cast concrete panels instead of on-site cutting of masonry eliminates silica dust generation.

When to Use: Always consider elimination first. Even if it appears more expensive initially, elimination often proves cost-effective by:

  • Preventing incidents entirely
  • Eliminating ongoing control maintenance costs
  • Reducing worker compensation insurance premiums
  • Improving productivity through safer, more efficient methods

Related: Detailed Elimination Guidance

Level 2: Minimize the Risk​

When elimination is not reasonably practicable, minimize risks using substitution, isolation, or engineering controls. These approaches reduce the risk at the source.

Substitution​

Replace the hazard with something less hazardous.

Substitution does not eliminate the hazard entirely but reduces the level of risk.

Construction Examples:

Substitute Materials:

  • Use water-based paints instead of solvent-based paints (reduces volatile organic compound exposure and fire risk)
  • Replace high-silica materials with low-silica alternatives where structural requirements permit
  • Use lower-noise equipment (hydraulic breakers instead of pneumatic jackhammers)

Substitute Processes:

  • Use mechanical fixings instead of chemical anchors to reduce exposure to resins and hardeners
  • Apply factory-applied coatings instead of on-site spray painting in confined areas
  • Use dry-cut systems with on-tool extraction instead of wet cutting (reduces slurry and cleanup hazards)

Substitute Equipment:

  • Replace chain slings with synthetic lifting slings (reduces crush and impact injury risks)
  • Use battery-powered tools instead of petrol-powered tools in enclosed areas (eliminates carbon monoxide exposure)

Related: Detailed Substitution Guidance

Isolation​

Separate people from the hazard using distance or barriers.

Isolation physically separates workers from the hazard without removing the hazard itself.

Construction Examples:

Physical Barriers:

  • Install guardrails and edge protection at floor penetrations and unprotected edges to prevent falls
  • Erect hoarding and barriers separating the construction site from public areas
  • Use exclusion zones around crane lift areas, demolition zones, or excavations

Remote Operation:

  • Operate plant remotely from a safe distance (e.g., remote-controlled demolition equipment)
  • Use long-reach tools to work from outside confined spaces or contaminated areas

Separate Storage:

  • Store incompatible chemicals in separate locations to prevent dangerous reactions
  • Keep flammable materials away from hot work areas and ignition sources

Time and Distance Separation:

  • Conduct noisy or dusty work outside normal hours when fewer workers are on site
  • Sequence high-risk activities so they do not occur simultaneously in adjacent areas

Related: Detailed Isolation Guidance

Engineering Controls​

Use physical modifications or mechanical devices to reduce risk.

Engineering controls involve changing the workplace, plant, or equipment to make the environment safer.

Construction Examples:

Guarding and Protection:

  • Machine guards on power tools preventing contact with moving parts (saw blades, grinding wheels)
  • Fall protection systems: guardrails, safety mesh, scaffold platforms
  • Overhead protection from falling objects

Ventilation Systems:

  • Local exhaust ventilation (LEV): Captures contaminants at the source (on-tool dust extraction for grinders and saws)
  • Dilution ventilation: General airflow reducing concentration of airborne contaminants in enclosed spaces

Dust and Fume Control:

  • Water suppression systems for cutting and grinding (reduces silica dust generation)
  • Integrated dust extraction on power tools
  • Enclosed and ventilated spray painting booths

Noise Reduction:

  • Sound dampening materials and enclosures around loud equipment
  • Mufflers and noise-reducing modifications to plant
  • Vibration isolation mounts reducing noise transmission

Electrical Safety:

  • Residual current devices (RCDs/safety switches) on all electrical equipment
  • Double insulation on portable power tools
  • Physical protection (conduits, cable covers) for electrical cables in high-traffic areas

Traffic Management:

  • Physical barriers separating pedestrians from vehicle operating areas
  • One-way traffic systems reducing reversing requirements
  • Designated crossings with boom gates or traffic lights

Ergonomic Modifications:

  • Height-adjustable work platforms reducing awkward postures
  • Mechanical assists for repetitive tasks (powered screwdrivers, nail guns)
  • Tool balancers suspending heavy tools to reduce sustained holding forces

Related: Detailed Engineering Controls Guidance

Level 3: Administrative Controls and PPE (Least Effective)​

When risks cannot be eliminated or adequately minimized through higher-level controls, use administrative controls and personal protective equipment (PPE) as additional protective layers.

[!warning] Limitations of Level 3 Controls Administrative controls and PPE are the least reliable because they:

  • Do not remove or reduce the hazard at the source
  • Rely entirely on consistent human behavior
  • Require ongoing supervision and reinforcement
  • Fail if workers do not follow procedures or wear PPE correctly

Never use Level 3 controls as the only protection when higher-level controls are reasonably practicable.

Administrative Controls​

Work methods, procedures, and organizational measures that reduce risk exposure.

Administrative controls change how people work but do not change the hazard itself.

Construction Examples:

Safe Work Procedures and SWMS: Documented procedures specifying how to perform tasks safely, including step-by-step instructions, required controls, and emergency procedures.

For high-risk construction work, Safe Work Method Statements (SWMS) are mandatory and must detail:

  • Work activities and sequence
  • Identified hazards
  • Risk assessment outcomes
  • Control measures (following hierarchy)
  • Person responsible for implementing controls

Permit Systems: Formal authorization processes ensuring controls are in place before high-risk work commences:

  • Confined space entry permits: Verify atmospheric testing, rescue arrangements, communication
  • Hot work permits: Confirm fire prevention measures, fire watch, flammable materials removed
  • Electrical work permits: Confirm isolation, testing, and authorized competent persons

Training and Competency: Ensuring workers understand hazards and safe work practices:

  • High-risk work licenses (scaffolding, rigging, dogging, crane operation, forklift)
  • Construction induction (White Card)
  • Task-specific training (working at heights, confined spaces, silica awareness)
  • Supervision of new and inexperienced workers

Signage and Communication: Visual warnings and information:

  • Hazard warning signs (asbestos, confined space, high voltage, falling objects)
  • Mandatory signs (PPE required, permit required, authorized access only)
  • Site induction boards showing emergency contacts and assembly points

Job Rotation and Rest Breaks: Limiting exposure duration for hazards that increase with time:

  • Rotating workers through tasks involving repetition or awkward postures
  • Scheduled rest breaks in shaded areas during extreme heat
  • Limiting daily exposure to high-noise environments

Housekeeping: Maintaining site cleanliness to reduce hazards:

  • Daily removal of off-cuts, debris, and rubbish
  • Immediate cleanup of spills
  • Organized material storage reducing trip hazards

Traffic Management Plans: Documented plans specifying vehicle routes, speed limits, pedestrian access, and control measures.

Related: Detailed Administrative Controls Guidance

Personal Protective Equipment (PPE)​

Equipment worn by workers to protect against specific hazards.

PPE creates a barrier between the worker and the hazard but does not reduce the hazard itself.

[!important] PPE Requirements (WHS Reg 44) If PPE is required, PCBUs must ensure it is:

  • Selected to minimize risk for the nature of work and hazards
  • Suitable in size, fit, and reasonably comfortable for the worker
  • Maintained to remain effective, clean, and in good working order
  • Supported by information, training, and instruction on proper use and storage

Construction PPE Examples:

Head Protection:

  • Hard hats protecting from falling objects and head strikes
  • Bump caps for low-clearance areas

Eye and Face Protection:

  • Safety glasses with side shields for general protection
  • Goggles for chemical splash or dust protection
  • Face shields for grinding, welding, or chemical handling

Hearing Protection:

  • Earplugs or earmuffs where noise exceeds safe levels and engineering controls are insufficient
  • Must provide adequate attenuation for the specific noise exposure

Respiratory Protection:

  • Disposable P2/P3 respirators for nuisance dust
  • Half-face respirators with P3 filters for silica dust (must be fit-tested)
  • Powered air-purifying respirators (PAPR) for extended use or higher protection
  • Supplied-air respirators for confined spaces with oxygen deficiency or toxic atmospheres

Hand Protection:

  • Cut-resistant gloves for handling sharp materials
  • Chemical-resistant gloves for handling chemicals (matched to substance)
  • Impact-resistant gloves for demolition and heavy work
  • Insulated gloves rated for electrical work

Foot Protection:

  • Steel-capped boots protecting from falling objects and punctures
  • Slip-resistant soles for wet or uneven surfaces

High Visibility Clothing:

  • Class D day-only vests for low-traffic areas
  • Class D/N day-night vests and long-sleeved shirts for high-traffic or roadwork areas

Fall Protection Equipment:

  • Safety harnesses with shock-absorbing lanyards connected to secure anchor points
  • Must be part of a complete fall arrest system (anchor, connector, harness, training, rescue plan)

Sun Protection:

  • Long-sleeved shirts, broad-brim hats, and sunscreen (SPF 50+) for outdoor work

[!warning] PPE Limitations PPE provides no protection if:

  • Not worn consistently (worker forgets or finds it uncomfortable)
  • Worn incorrectly (respirator not fitted properly, safety glasses fogged and removed)
  • Not maintained (damaged hard hat, torn gloves, expired respirator filters)
  • Wrong type for the hazard (using disposable dust mask instead of fitted respirator for silica)

Related: Detailed PPE Guidance

Combining Control Measures​

Effective risk control typically uses multiple measures from different hierarchy levels, creating layers of protection.

Example: Controlling Silica Dust from Concrete Cutting

Level 1 - Elimination:

  • Specify pre-cut openings in concrete panels during manufacture (eliminates on-site cutting)

Level 2 - Substitution:

  • Use diamond blades designed for wet cutting with integrated water feed (reduces dust generation)

Level 2 - Engineering:

  • On-tool water suppression delivering constant water flow to the blade
  • On-tool vacuum extraction capturing dust at the source

Level 2 - Isolation:

  • Erect physical barriers separating cutting area from other work zones
  • Conduct cutting work during periods when fewer workers are on site

Level 3 - Administrative:

  • Limit cutting tasks to short durations with rest breaks
  • Train workers on silica hazards and proper use of controls
  • Maintain water suppression systems and replace worn blades promptly

Level 3 - PPE:

  • Fit-tested P3 respirators for workers performing cutting (as final protective layer)

This layered approach provides redundancy—if water suppression fails, extraction and PPE remain effective.

Implementing Controls​

Develop Work Procedures​

Create safe work procedures documenting:

  • Task description and sequence of steps
  • Identified hazards at each step
  • Control measures to be implemented
  • Emergency procedures if something goes wrong

For high-risk construction work, this is formalized in the SWMS.

Provide Training and Information​

Workers must be competent to perform tasks safely:

  • Information: Explain the hazards, why controls are necessary, and consequences of non-compliance
  • Instruction: Demonstrate how to perform tasks safely and use controls correctly
  • Training: Workers practice under supervision until competent
  • Verification: Workers demonstrate competency (not just sign acknowledgment)

Provide training in a format workers can understand (language, literacy considerations).

Ensure Adequate Supervision​

Supervision level depends on:

  • Risk level: High-risk work requires close supervision
  • Worker experience: New workers need closer supervision than experienced workers
  • Task complexity: Complex or infrequent tasks need more supervision

Supervisors must be competent to recognize unsafe conditions and take corrective action.

Maintain Controls​

Establish maintenance schedules ensuring controls remain effective:

  • Plant and equipment: Regular inspection, testing, and maintenance (e.g., RCD testing, scaffold inspections)
  • PPE: Cleaning, inspection, and replacement of damaged items
  • Engineering controls: Ventilation system filters replaced, water suppression nozzles cleared
  • Administrative controls: Procedures updated, refresher training conducted

Assign responsibility and keep maintenance records.

Cost Considerations and Reasonably Practicable​

Cost can be considered when determining what is reasonably practicable, but:

  • Cannot be used as a reason for doing nothing
  • Greater the risk, less weight given to cost
  • If two controls provide equal protection and reliability, choose the less expensive
  • Cost cannot justify using Level 3 controls when higher-level controls are available

Example: Edge Protection

Options:

  1. Guardrails (Level 2 - Engineering): $15,000 for full perimeter protection
  2. Safety harnesses (Level 3 - PPE): $2,000 for harnesses + anchor installation

Even though guardrails cost more, they are reasonably practicable because:

  • They provide more reliable protection (workers cannot forget to wear them)
  • Edge protection is a well-established, proven control for fall risks
  • The severity of potential harm (death from fall) is extreme
  • Cost is not grossly disproportionate to the risk

Guardrails must be used. Harnesses alone would not satisfy the duty.

Summary​

The Hierarchy of Control provides a systematic approach to managing WHS risks:

Level 1 (Elimination) is always preferred as it removes risk entirely.

Level 2 (Substitution, Isolation, Engineering) minimizes risk at the source when elimination is not reasonably practicable.

Level 3 (Administrative and PPE) provides additional protection but is least reliable on its own.

Effective control combines multiple measures from different levels, creating layered protection.

Implementation requires documented procedures, competent workers, adequate supervision, and ongoing maintenance.

Once controls are implemented, proceed to Step 4 to review and ensure they remain effective over time.