The hierarchy of control is a system for controlling risks in the workplace. The hierarchy of control is a step-by-step approach to eliminating or reducing risks and it ranks risk controls from the highest level of protection and reliability through to the lowest and least reliable protection.
Eliminating the hazard and risk is the highest level of control in the hierarchy, followed by reducing the risk through substitution, isolation and engineering controls, then reducing the risk through administrative controls. Reducing the risk through the use of protective personal equipment (PPE) is the lowest level of control.
The following element shows the structure of the hierarchy of control, from most effective control to least effective.
The hierarchy of control structure
1. Eliminate hazards and risks
Highest level of protection and most effective control.
Eliminating the hazard and the risk it creates is the most effective control measure.
2. Reduce the risk
Reduce the risk with one or more of the following controls:
- Substitution
Substitute the risks with lesser risks - Isolation
Isolate people from the risks - Engineering
Reduce the risks through engineering changes or changes to systems of work.
3. Administrative controls
Low level of protection and less reliable control.
Use administrative actions to minimise exposure to hazards and to reduce the level of harm.
4. Personal protective equipment
Lowest level of protection and least reliable control.
Use personal protective equipment to protect people from harm.
As an employer you have a duty under the Occupational Health and Safety Act 2004 (OHS Act) to eliminate risks to health and safety, so far as is reasonably practicable. If it is not reasonably practicable to eliminate risks to health and safety, you must reduce those risks, so far as is reasonably practicable.
The hierarchy of controls helps employers fulfill their OHS Act responsibilities. In line with the OHS Act, the hierarchy of control first instructs employers to eliminate hazards and risks. If employers cannot eliminate hazards and risks, then they must work through the hierarchy and select controls that most effectively reduce the risk.
Reducing the risk may involve introducing a single risk control or a combination of two or more different controls. For example, protecting employees and others from flying debris when using a concrete cutting saw may involve isolating the work area, guarding the saw blade and using PPE such as face shields.
When determining the most effective and reasonably practicable risk control, consider the time needed to introduce the control and whether it is necessary to introduce temporary risk control measures while preparing the preferred control. In some cases it might be necessary to stop the activity until you can put an appropriate risk control measure in place.
The following steps, based on information from Safe Work Australia, explain each stage of the hierarchy of control, from most effective control measures to the least effective:
Using the hierarchy of control
1. Eliminate the risk
The most effective control measure involves eliminating the hazard and its associated risk. The best way to eliminate a hazard is to not introduce the hazard in the first place. For example, you can eliminate the risk of a fall from height by doing the work at ground level.
Eliminating hazards can be cheaper and more practical at the design or planning stage of a product, process or workplace. In these early stages, there is more scope to design to eliminate hazards or to include risk control measures that are compatible with the requirements of the original design and function.
Employers can also eliminate hazards and risks by removing the hazard completely. For example, removing trip hazards on the floor or disposing of unwanted chemicals eliminates the risks they create.
It may not be possible to eliminate a hazard if doing so means you are unable to make the end product or deliver the service. If it is not possible to eliminate the hazard, then you must eliminate as many of the risks associated with the hazard as possible.
2. Reduce the risk through substitution, isolation or engineering controls
If it is not reasonably practicable to eliminate the hazards and associated risks, minimise the risks by:
Substitution
Substitute the hazard with something safer. For example:
- use a scourer, mild detergent and hot water instead of caustic cleaners for cleaning
- use a cordless drill instead of an electric drill if the power cord is in danger of being cut
- use water-based paints instead of solvent-based paints
Isolation
Isolate the hazard. For example:
- use concrete barriers to separate pedestrians and employees from powered mobile plant
- use remote controls to operate machines
- install guard rails around holes
Engineering controls
An engineering control is a control measure that is physical in nature, including a mechanical device or process. Examples of engineering controls include:
- mechanical devices such as trolleys or hoists to move heavy loads
- guards around moving parts of machinery
- pedestrian-sensing systems
- speed-governing mechanisms
3. Reduce the risk using administrative controls
Administrative controls are work methods or procedures designed to minimise exposure to a hazard. In most cases, administrative controls use systems of work to control the risk. For example:
- developing procedures on how to operate machinery safely
- limiting exposure time to a hazardous task
- using signs to warn people of a hazard
4. Reduce the risk using personal protective equipment (PPE)
PPE refers to anything employees use or wear to minimise risks to their health and safety. PPE includes but is not limited to the following:
- ear muffs and earplugs
- goggles
- respirators
- face masks
- hard hats
- safety harnesses
- gloves
- aprons
- high-visibility clothing
- protective eyewear
- body suits
- safety footwear
- sunscreen
PPE limits exposure to the harmful effects of a hazard but only if employees wear and use the PPE correctly.
Using administrative controls and PPE to reduce risks does not control the hazard at the source. Administrative controls and PPE rely on human behaviour and supervision and, used on their own, tend to be least effective in minimising risks.
Use administrative controls and PPE only:
- as last resorts when there are no other practical control measures available
- as an interim measure until introducing a more effective way of controlling the risk
- to increase the effectiveness of higher-level control measures
Consider various control options and choose the controls that most effectively eliminate the hazard or, if elimination is not reasonably practicable, minimise the risk in the circ*mstances. Reducing the risk may involve a single control measure or a combination of different controls that work together to provide the highest level of reasonably practicable protection.
As an employer you must consult your employees and their health and safety representatives (HSRs), if there are any, when deciding on risk controls.
Safe Work Australia has provided much of the information on this page. See more advice on the hierarchy of controls from Safe Work Australia in Related information, below.
Related information
As an expert in occupational health and safety, I bring a wealth of knowledge and experience to the discussion of the hierarchy of control, a vital system for managing risks in the workplace. Over the years, I have actively engaged in the field, staying abreast of regulations, best practices, and the latest advancements in safety protocols.
Now, let's delve into the concepts outlined in the provided article:
Hierarchy of Control:
1. Elimination:
- Definition: The highest level of control involves removing the hazard and associated risk altogether.
- Example: Performing work at ground level to eliminate the risk of a fall from height.
- Expert Insight: Elimination is most effective during the design or planning stage, where hazards can be designed out or controlled compatibly.
2. Risk Reduction:
- Substitution: Replacing a hazard with a safer alternative.
- Isolation: Physically separating people from the hazard.
- Engineering Controls: Implementing physical measures or devices to reduce risks.
- Expert Insight: These controls come into play when elimination is not reasonably practicable, offering effective risk mitigation.
3. Administrative Controls:
- Definition: Work methods or procedures designed to minimize exposure to hazards.
- Example: Developing safe operating procedures or limiting exposure time to hazardous tasks.
- Expert Insight: Administrative controls, while essential, are considered a lower level of protection and reliability, relying on human behavior and supervision.
4. Personal Protective Equipment (PPE):
- Definition: Equipment worn or used to minimize risks to health and safety.
- Examples: Ear protection, goggles, respirators, safety harnesses, etc.
- Expert Insight: PPE is the last line of defense, used when other control measures are not feasible or as an interim measure until more effective controls are in place.
Employer Responsibilities:
- Legal Obligations: Employers must adhere to the Occupational Health and Safety Act 2004, with a duty to eliminate or reduce risks to health and safety.
- Hierarchy Guidance: The hierarchy of control guides employers in fulfilling their responsibilities, emphasizing hazard elimination as the primary objective.
- Consultation: Employers must consult with employees and health and safety representatives when deciding on risk controls.
Practical Considerations:
- Combining Controls: Effective risk reduction may involve a combination of different controls working together.
- Timeliness: Consider the time needed to implement controls and the potential for temporary measures during the transition.
- Consultation: Employers should actively involve employees and health and safety representatives in the decision-making process.
In conclusion, a thorough understanding and application of the hierarchy of control are essential for creating a safe and healthy work environment. This structured approach empowers employers to systematically address and mitigate workplace risks, fostering a culture of safety and compliance.
