Hazardous substances: Safety basics

Understand your hazardous substances and how to manage them.


What are hazardous substances

Hazardous substances are substances that can harm people's health. They may be solids, liquids or gases. In the workplace, they are often in the form of fumes, dusts, mists and vapours.

  • acute toxins such as cyanide
  • substances harmful after repeated or prolonged exposure such as mercury and silica
  • corrosives such as sulphuric acid and caustic soda
  • irritants such as ammonia
  • sensitising agents such as isocyanates
  • cancer-causing substances (carcinogens) such as benzene and vinyl chloride

Health effects of hazardous substances

You can inhale hazardous substances or absorb them through the skin. They can cause immediate and long-term health problems. Health effects include poisoning, irritation, chemical burns, sensitisation, cancer and birth defects. Hazardous substances can also cause diseases of organs such as the skin, lungs, liver, kidneys and nervous system.

Safety data sheets and labels

Manufacturers and importing suppliers must provide safety data sheets (SDSs) with a hazardous substance, and correctly label them consistent with the Occupational Health and Safety Regulations 2017 (OHS Regulations).

SDSs have information about the substance and precautions for safe use. Labels must include the name, address and contact telephone number of the Australian manufacturer or importing supplier.

Globally Harmonized System of Classification and Labelling of Chemicals

SDSs and labels follow the Globally Harmonized System of Classification and Labelling of Chemicals (GHS). It's an international system for categories and warnings for hazardous substances.

Are you using hazardous substances

A good approach is to audit the substances in your workplace. Then you can work out which ones are classed as hazardous, carcinogenic or even prohibited.

To understand the hazardous substance you're working with, use the SDS and the label. An SDS will give you information about, for example:

  • what's in the product
  • potential health hazards
  • first aid treatment
  • precautions for use
  • safe handling information
  • an Australian contact point

Employers must:

  • keep a register of all the hazardous substances in the workplace
  • have the current SDSs for them and make them available to employees
  • not change the information on a SDS
  • ensure that containers in which hazardous substances are supplied are labelled
  • identify containers of waste

Controlling risks

The Code of practice: Hazardous substances has information to help you check if you have any hazardous substances, and contains details about hazards, risks and controls.


Involving your employees in health and safety issues can result in a safer workplace. That's why consultation is an important part of risk management. In certain situations employers must consult about health and safety issues with employees and health and safety representatives (HSRs) if they have them. See 'consultation' for detailed information.

Find the hazards and assess risks

Auditing the substances in your workplace and checking the SDSs and labels will help you find the hazards related to hazardous substances in your workplace. You then need to assess the health and safety risks.

How much risk there is working with a hazardous substance depends on the substance (form, concentration, toxicity, health effects and physical and chemical properties), or work (how you’re using or handling it, quantities and routes of exposure).

You may need to do atmospheric monitoring to check if airborne hazards exceed exposure limits.

Control risks

Work through the following list to control hazardous substances risks. The OHS Regulations 2017 (OHS Regulations) set out specified risk control measures, to be used in order. This is called the hierarchy of control.

  • The best option is to eliminate the hazardous substance completely. For example, you could use a physical process rather than a chemical process to clean something.
  • If you can’t eliminate the risk associated with a hazardous substance, your next steps are to use a safer substance, isolation or using engineering controls. For example, use a detergent instead of a chlorinated solvent for cleaning, or install exhaust extraction to remove contaminants.
  • If any risk remains, you can use administrative controls to reduce the risk in relation to the way the work is done. For example, reduce how many employees are exposed to the substance by doing the task out of hours.
  • If any risk remains after these have been done, you can use personal protective equipment to reduce the risk. For example, give employees respirators.

Review risk controls

Review your risk controls to make sure they are working properly. You must review and, if needed revise them if, for example:

  • there are changes to the way work is done, such as changes to plant, equipment or substances
  • a notifiable incident occurs
  • an HSR requests

Health monitoring

If employees are exposed to certain hazardous substances which may have an adverse effect on their health, you must do health monitoring and keep a record of the results.

Health and safety legal duties

The Occupational Health and Safety Act 2004 sets out duties in relation to health and safety in the workplace. The OHS Regulations have specific duties about hazardous substances.

Licences to use scheduled carcinogens

Under the OHS Regulations, you need a licence from WorkSafe to use certain carcinogenic substances.

More information