ALARP & SFAIRP
SFAIRP (So Far As Is Reasonably Practicable) and ALARP (As Low As Reasonably Practicable) are risk management principles requiring you to reduce risks to the lowest level achievable unless the cost of further controls is grossly disproportionate to the safety benefit. SFAIRP is the legal duty under Australian WHS law; ALARP is the engineering framework commonly used in high-hazard industries.
What is SFAIRP?
SFAIRP is the core legal standard embedded in Section 18 of the Model Work Health and Safety Act 2011. When the Act requires you to ensure safety "so far as is reasonably practicable," it's asking you to do everything reasonable to control risk—not just the minimum, not just what's affordable.
This isn't a simple cost-benefit calculation. The law deliberately tips the scales toward safety by requiring "gross disproportion"—the cost of a control must vastly outweigh the risk reduction before you can reject it.
SFAIRP transforms workplace safety from a compliance checklist into a continuous, evidence-based duty. As technology improves and knowledge advances, what's "reasonably practicable" changes. You must keep pace.
What is ALARP?
ALARP originated in UK engineering and is widely used in Australian rail, offshore petroleum, aviation, and mining sectors. While SFAIRP asks "Have you done everything reasonable?", ALARP asks "Is the residual risk tolerable?"
ALARP often uses a "tolerability of risk" framework with three zones: unacceptable (work must stop), tolerable (continue only if risk is ALARP), and broadly acceptable (negligible risk). Your goal is to push risks down through higher-level controls using the hierarchy of controls.
Regulators like ONRSR and NOPSEMA treat SFAIRP and ALARP as operationally equivalent—when properly applied, achieving SFAIRP results in risk being ALARP. However, the legal duty always rests on SFAIRP. Achieving a quantitative ALARP target won't protect you if further controls were reasonably practicable.
SFAIRP vs ALARP: understanding the difference
These aren't competing standards—they're complementary lenses on the same safety challenge. Understanding the distinction helps you apply both correctly.
| Feature | SFAIRP | ALARP |
|---|---|---|
| Primary Domain | Legal & Statutory (WHS Act, Courts) | Engineering & Technical (Rail, Oil & Gas) |
| Core Question | "Have you done everything reasonable?" | "Is the residual risk tolerable?" |
| Focus | Measures & Conduct (Input) | Risk State & Outcome (Output) |
| Legal Status | Binding legal test in Australian WHS law | Framework often accepted as demonstrating SFAIRP |
How SFAIRP works: Section 18 of the WHS Act
Section 18 breaks "reasonably practicable" into a structured legal test. You must consider five factors in sequence, weighing them against each other.
The five factors
| Factor | What You Must Consider | Practical Application |
|---|---|---|
| 1. Likelihood | Probability of the hazard occurring | Don't underestimate rare events if they're catastrophic. Even low-probability risks require controls if consequences are severe. |
| 2. Degree of Harm | Potential severity (consequence) | Focus on the worst credible outcome—fatality or permanent disability—not just the most likely minor injury. |
| 3. Knowledge | What you know or ought to know about the risk | Actively seek industry alerts, standards, and regulator guidance. Ignorance is not a defence. |
| 4. Availability | Availability and suitability of controls | Is the control physically possible and appropriate for your context? If not, find suitable alternatives. |
| 5. Cost | Cost versus risk reduction | Only reject controls if cost is grossly disproportionate to the risk. This is a high bar. |
The gross disproportion test
This test comes from the 1949 UK case Edwards v National Coal Board, where Lord Asquith established that risks can only be left uncontrolled if there's a "gross disproportion" between the cost of control and the safety benefit.
You're not comparing one dollar of cost to one dollar of benefit. The cost must vastly outweigh the risk reduction—often by a factor of 3 to 10 times or more, depending on risk severity.
For high-consequence risks like potential fatalities, it's almost impossible to justify inaction based on cost alone. The law demands a "transparent bias" toward safety.
Track risk assessments, control decisions, and evidence of due diligence with WorkSafeKit's integrated safety management system.
Applying the hierarchy of controls
SFAIRP compliance requires you to work systematically through the hierarchy of controls. WHS Regulation 36 explicitly requires you to start at the top and only move down if higher-level controls aren't reasonably practicable.
| Level | Control Type | Effectiveness | Example |
|---|---|---|---|
| 1 | Elimination | 100% | Removing level crossings; automating manual tasks |
| 2 | Substitution | High | Using water-based paints instead of solvents |
| 3 | Isolation | High | Installing barriers between vehicles and pedestrians |
| 4 | Engineering | Medium | Machine guards, interlocks, ventilation systems |
| 5 | Administrative | Low | Training, procedures, signage, permits |
| 6 | PPE | Low | Hard hats, safety glasses, respirators |
Over-reliance on administrative controls and PPE is a common SFAIRP failure. Courts consistently reject "we trained the worker" arguments when physical hazards could have been eliminated or isolated through engineering controls.
If you can eliminate the hazard and the cost isn't grossly disproportionate, settling for lower-level controls is a breach of your duty.
Officer duties and due diligence
The WHS Act places personal duties on Officers—directors, CEOs, CFOs, and senior managers who make decisions affecting the business. Section 27 requires you to exercise due diligence to ensure your PCBU complies with WHS duties.
What due diligence requires
| Requirement | What You Must Do | Common Failure Mode |
|---|---|---|
| Knowledge | Keep up-to-date with WHS matters | Relying on "common sense" or outdated practices |
| Understanding | Understand your business's specific risks | "I'm just the accountant/investor; I don't know operations" |
| Resources | Ensure appropriate resources for safety | Cutting safety budgets without SFAIRP analysis |
| Reporting | Ensure processes for receiving safety information | Only looking at "Green" KPIs, ignoring incident reports |
| Compliance | Ensure legal compliance processes exist | Failing to consult workers or report notifiable incidents |
| Verification | Verify resources and processes are actually used | Assuming the safety manual is followed without checking |
Verification is critical. "Paper safety"—comprehensive manuals that aren't followed in practice—offers no protection. Officers must conduct site visits, review real work, and confirm documented systems match reality.
If you deny a budget request for safety controls without documented gross disproportion analysis, you're personally liable for any resulting incident.
Real-time dashboards, automated compliance tracking, and evidence-based reporting for board-level oversight.
Common failures and industrial manslaughter
The consequences of SFAIRP failure have escalated with industrial manslaughter laws now in force in Queensland, Victoria, Western Australia, and the ACT. Maximum penalties include up to 20 years imprisonment for individuals and fines exceeding $10 million for corporations.
Reverse engineering risk assessments
One of the most serious failures is "reverse engineering"—deciding on a design or budget first, then manipulating the risk assessment to justify it. Regulators call this fraud.
If discovered during an investigation, it destroys the credibility of your entire safety case and demonstrates conscious disregard for safety—the threshold for criminal negligence.
Paper safety versus real safety
Producing comprehensive procedures and SWMS that aren't followed in practice is another common failure. SFAIRP requires effective implementation, not just documentation.
A 100-page safety plan sitting on a shelf offers no defence. Your systems must be verified, trained, supervised, and genuinely used.
Case example: Brisbane Auto Recycling (2020)
Australia's first industrial manslaughter conviction involved a worker killed by a reversing forklift. The business had no traffic management plan, the driver was unlicensed, and directors knew of the risks but prioritised profit over safety.
The court found the cost of controls—barriers, signage, licensed operators—was negligible compared to the risk of death. There was no gross disproportion, just negligence. The company was fined $3 million and directors received suspended prison sentences.
The judgment emphasised that post-incident attempts to "dishonestly evade responsibility" increased moral culpability. Transparency and integrity in your SFAIRP process matter in court.
Best practices for demonstrating SFAIRP
Document your decision-making process
While the law doesn't mandate a specific "SFAIRP Report," you must be able to prove you went through the process. For significant risks or design changes, maintain documented risk assessments, hazard logs, and decision registers.
If it isn't written down, courts may assume it didn't happen. Your documentation should show what controls you considered, why you selected some and rejected others, and evidence of the gross disproportion test if cost influenced your decision.
Keep pace with state of knowledge
Subscribe to regulator alerts, industry standards updates, and manufacturer safety notices. What you "ought reasonably to know" includes the collective knowledge of your industry.
If a competitor or trade association identifies a control measure, you're presumed to know about it. Maintain evidence that you actively monitor external knowledge sources.
Avoid over-reliance on quantitative risk assessment
For complex projects, Quantitative Risk Assessment (QRA) can support decision-making. However, regulators warn against treating QRA results as facts rather than estimates.
QRA inputs—failure rates, human error probabilities—are often uncertain. A QRA showing risk is "tolerable" doesn't override your duty to implement further controls if they're reasonably practicable.
Apply controls using the hierarchy
Work systematically down the hierarchy of controls. For each hazard, ask: "Can we eliminate this? If not, can we substitute, isolate, or engineer it out?"
Only after exhausting higher-level options should you rely on administrative controls or PPE. Document why higher-level controls weren't reasonably practicable—and be prepared to defend that analysis.
Verify, don't just audit
Officers must verify that documented systems match reality. This means site visits, observing actual work, interviewing workers, and interrogating incident data—not just reviewing compliance dashboards.
If your risk register says a hazard is "controlled" but workers report issues, the gap is your problem to close.
Frequently Asked Questions
If I comply with Australian Standards, have I met my SFAIRP duty?
Not necessarily. Standards represent minimum acceptable requirements at the time they were written. SFAIRP is dynamic—if newer technology or methods are safer and reasonably practicable, you must implement them. Standards are the floor, not the ceiling.
Can I use cost as a reason not to implement a safety control?
Only if the cost is grossly disproportionate to the risk reduction—typically 3 to 10 times higher or more, depending on risk severity. You can't simply argue the control is "too expensive" or "not in the budget." If the risk is high, it's almost impossible to justify inaction based on cost alone.
What's the difference between "practicable" and "reasonably practicable"?
"Practicable" means physically possible with current technology. "Reasonably practicable" introduces the weighing of factors including cost, likelihood, and consequence. Something might be practicable but not reasonably practicable if the cost is grossly disproportionate to the risk.
Do I need a SFAIRP report for every decision?
The law doesn't mandate a specific document format, but you must demonstrate you went through the SFAIRP process. For significant risks or design changes, a documented risk assessment, hazard log, or decision register is essential evidence of due diligence.
How does SFAIRP apply to legacy assets?
There are no "grandfather rights" under WHS law. You must assess the gap between current standards and your legacy asset. If upgrading is grossly disproportionate, implement interim controls (speed restrictions, increased inspections) to demonstrate SFAIRP until permanent upgrades are feasible.
Are SFAIRP and ALARP legally the same in Australia?
Regulators treat them as operationally equivalent, but SFAIRP is the binding legal standard. Achieving a quantitative ALARP target won't protect you in court if further controls were available, effective, and not grossly disproportionate.
References and Further Reading
Work Health and Safety Act 2011 (NSW), particularly Section 18 (meaning of reasonably practicable), Section 19 (primary duty of care), and Section 27 (due diligence for officers).
Safe Work Australia, How is 'reasonably practicable' defined? (Interpretive Guideline), provides the authoritative interpretation of Section 18.
Safe Work Australia, How to Determine What is Reasonably Practicable to Meet a Health and Safety Duty (2013), offers practical guidance for applying the five factors.
WorkSafe Western Australia, Demonstration of Risk Reduction So Far As Is Reasonably Practicable (2024), provides detailed methodology for SFAIRP demonstrations in high-hazard industries.
Transport for NSW, Safety So Far As Is Reasonably Practicable: What Does It Mean? (2016), discusses SFAIRP application in rail safety under ONRSR.
NOPSEMA, ALARP Guidance Note (2021), explains ALARP application in offshore petroleum safety cases.
Edwards v National Coal Board [1949] 1 KB 704 (Court of Appeal, England and Wales), the seminal case establishing the gross disproportion test and modern interpretation of "reasonably practicable."
Safe Work Australia, Guide to the Work Health and Safety Act (2011), provides context on the Robens philosophy and shift from prescriptive to performance-based regulation.
Queensland Industrial Relations Commission, R v Brisbane Auto Recycling Pty Ltd (2020), Australia's first industrial manslaughter conviction—critical reading for understanding consequences of SFAIRP failure.
Rae, A.J., et al. (2022), "Gross Disproportion, Step by Step", Hazards 29, IChemE Symposium Series, provides practical methodology for applying disproportion factors in quantitative assessments.
R2A Due Diligence Engineers, SFAIRP Not Equivalent to ALARP (2024), discusses the legal and operational distinctions between the two frameworks.