What is ALARP?

ALARP stands for “As Low As Reasonably Practicable.” It is a principle used in risk management, particularly in health and safety, to reduce risks to a level that is as low as is reasonably practicable. This concept balances the level of risk against the time, effort, and cost needed to further reduce that risk. The goal is to minimise risk to a point where the cost and effort required to reduce the risk further would be grossly disproportionate to the additional risk reduction achieved.

What is SFAIRP?

You may also come across SFAIRP which stands for “So Far As Is Reasonably Practicable”. This is a term widely used in the Health and Safety at Work etc Act and in other regulations. As far as the HSE is concerned, ALARP and SFAIRP are interchangeable unless used in a legal document in which case the correct term must be used.

ALARP Key Points

The ALARP principle is based on the following key concepts:

Risk Assessment:

Risks are identified and assessed in terms of their potential impact and likelihood.

Risk Tolerability:

The idea is that some level of risk can be tolerated, as long as it is properly managed and reduced to a level that is as low as reasonably practicable.

Risk Reduction:

Measures to reduce risks are considered and implemented if they are reasonably practicable.

Reasonably Practicable:

The concept of what is “reasonably practicable” takes into account factors such as the cost, time, effort, and difficulty of implementing risk reduction measures, as well as the potential benefits and consequences of those measures.

Gross Disproportion:

The notion that the cost and effort required to reduce a risk further must not be grossly disproportionate to the additional risk reduction achieved.

To implement controls costing £1m to prevent the risk of someone suffering light bruising is grossly disproportionate

To spend £1m on controls to prevent a major explosion which has the potential to injure or kill hundreds of people is obviously proportionate.

The ALARP Hierarchy

The ALARP hierarchy is a framework that guides the decision-making process in risk management. It consists of three main levels:

Unacceptable Region:

Risks that are deemed unacceptable and must be reduced, regardless of the cost or effort involved.

ALARP Region:

Risks that are tolerable, but should be reduced to a level that is as low as reasonably practicable.

Broadly Acceptable Region:

Risks that are so low that no further action is required, and they are considered to be adequately controlled.

ALARP and Legal Requirements

The concept of “reasonably practicable” is central to UK Health and Safety law. It is central to the general duties under the Health and Safety at Work etc. Act 1974 and various health and safety regulations enforced by HSE and Local Authorities.

Regulations, ACOPs, guidance, campaigns, etc. should always be based on what is reasonably practicable.

ALARP in Practice: Steps to Conducting a Risk Assessment

Implementing the ALARP approach in a risk assessment involves the following steps:

  1. Hazard Identification:

    Systematically identify all potential hazards and their associated risks.

  2. Assess Risks:

    Assess the likelihood and severity of the identified risks.

  3. Risk Evaluation:

    Determine whether the risks are within the ALARP region or require further reduction.

  4. Risk Reduction:

    Implement appropriate control measures to reduce the risks to a level that is as low as reasonably practicable.

  5. Monitoring and Review:

    Continuously monitor the effectiveness of the control measures and review the risk assessment as necessary.

How Do You Determine if a Risk Has Been Reduced to ALARP?

Determining whether a risk has been reduced to ALARP involves a careful balancing act. You must consider the following factors:

  1. Likelihood and Severity:

    The remaining likelihood and severity of the risk after implementing control measures.

  2. Cost and Effort:

    The cost, time, and effort required to further reduce the risk.

  3. Gross Disproportion:

    Whether the cost and effort to further reduce the risk would be grossly disproportionate to the additional risk reduction achieved.

ALARP Case Study

To illustrate the practical application of the ALARP approach, let’s consider an example:

In a manufacturing plant, a risk assessment might identify a potential hazard from machinery. The initial control measure might be to install safety guards. To determine if the risk is ALARP, the company would evaluate if additional measures, such as advanced sensor systems or enhanced training for workers, would significantly reduce the risk compared to the cost and effort required. If the additional measures are not justified by the level of risk reduction they provide, the risk is considered ALARP with the implemented safety guards.

Challenges and Limitations of ALARP

While the ALARP approach offers numerous benefits, it is not without its challenges and limitations. Some of the key issues include:

  • Subjectivity in Decision-Making:

    Determining what is “reasonably practicable” can be subjective and may vary depending on the decision-maker’s experience and risk tolerance.

  • Difficulty in Quantifying Risks:

    Accurately quantifying the likelihood and severity of certain risks can be challenging, particularly for complex or emerging hazards.

  • Balancing Competing Priorities:

    Reconciling the need to reduce risks with other business priorities, such as cost, productivity, and operational efficiency, can be a delicate balance.

  • Uncertainty in Future Conditions:

    Changes in technology, regulations, or external factors can affect the validity of the ALARP assessment over time, requiring regular review and updates.


In conclusion, the ALARP principle is a fundamental concept in risk assessment that helps organisations systematically identify, evaluate, and reduce risks to a level that is as low as reasonably practicable. By understanding and implementing the ALARP approach, you can enhance safety, ensure compliance with regulations, and make informed, cost-effective decisions that protect your employees, customers, and the general public.

Find out more about ALARP and managing risk with our accredited Risk Assessment Traiining Course.

Published On: June 11th, 2024