High-pressure water jetting

WorkSafe is reminding employers and employees of the risks associated with high-pressure water jetting.



In the past two years, employees have been seriously injured in two high-pressure water jetting incidents in Victoria.

High-pressure water jetting uses a stream of pressurised water to remove material, debris or other things from surfaces, including drains and pipes. The equipment is often called a high-pressure water cleaner, hydro jetter or drain cleaner.

Safety Issues

The main risks in high-pressure water jetting are:

  • the water jet may pierce the skin
  • contaminated material may be injected into the body
  • flying debris may hit and injure a person (including eye injuries)
  • a flailing hose, an out of control nozzle or a separated hose coupling may hit a person

Other hazards may include:

  • loud noise exposure
  • working in confined spaces
  • fall hazards
  • respiratory and eye hazards through hazardous chemicals and biological material exposure
  • electric shock

Controlling risks

The Australian Standard for high-pressure water jetting systems (AS4233.1) defines classes of high-pressure water jetting systems. It also gives guidance for maintenance, repair and use of high-pressure water jetting systems and details training for safe operation and personal protection.

Class A high-pressure water jetting systems are systems with an output capability range of 800 to 5600 bar litres per minute.

Class B high-pressure water jetting systems are systems with an output capability of more than 5600 bar litres per minute. Class B systems are readily available and widely used, highly powered systems that present a higher risk to the operator.

Summary of AS4233.1 key points

Maintenance and repair

Operators that use high-pressure water jetting systems should not modify jetting equipment or its attachments without the manufacturer or other competent person's written approval. Class B equipment should only be modified a competent person with appropriate engineering skills and must be consistent with safety recommendations.

Only the manufacturer, their agent or competent persons should conduct repairs or maintenance on high-pressure water jetting equipment.

Personal Protective Equipment (PPE)

Employers need to identify hazards and do a risk assessment of the work being carried out to decide what PPE is required for the task. Suitable PPE should always be worn where identified hazards cannot be prevented or suitably controlled. Where PPE is issued, employers must provide instruction and training on its correct use and maintenance.

Personal eye protection should always be worn when an employee is near jetting operations. The employee in direct control of the flow of water should, as a minimum, wear safety glasses and a face shield.

Head protection should be worn where needed.

Leg and body armour made from material that can stand the direct force of the water jet should be worn by water jetting operators where there is risk of injury.

Personal hearing protectors should be worn where noise hazards cannot be controlled.


  • General: Operators should be given training on high-pressure water jetting operations by a competent person. The training should include the importance of all parts, fittings and hoses being the right size, compatible and rated equal to or more than the equipment's maximum operational pressure. This lowers the chance of equipment failures that can cause serious injury.
  • Class B: All operators should be trained and assessed as competent to operate Class B equipment. Training must be given through a Registered Training Organisation (RTO) and meet the high-pressure water jetting units of competency. Trainers must be accredited by an RTO and have at least 5 years' relevant water jetting experience.
  • Refresher training: Competency or refresher training on high-pressure water jetting operations must be done and recorded at least every two years, to ensure operators remain competent. Refresher or extra training should be given when using new or more powerful equipment or introducing new technology.

Legal duties

Employers have duties under the Occupational Health and Safety Act 2004. They must, so far as is reasonably practicable: 

  • provide and maintain a working environment that is safe and without risks to the health of employees and independent contractors
  • provide employees with the necessary information, instruction, training or supervision to enable them to do their work in a way that is safe and without risks to health
  • ensure that persons other than employees are not exposed to risks to their health or safety arising from the employer's conduct
  • consult with employees and health and safety representatives when identifying or assessing hazards or risks and making decisions about risk control measures

The Occupational Health and Safety Regulations 2017 requires employers to ensure that employees and persons supervising the employees are trained and given information and instruction about hazards related to plant, including:

  • the processes for identifying hazards and controlling risk; and
  • safety procedures associated with using the plant at the workplace; and
  • the use, fit, testing and storage of PPE, if relevant

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