What do you call the systematic approach used to decide on the level of care needed following an injury or other health concern in acute care?

The meaning of the word hazard can be confusing. Often dictionaries do not give specific definitions or combine it with the term "risk". For example, one dictionary defines hazard as "a danger or risk" which helps explain why many people use the terms interchangeably.

There are many definitions for hazard but the most common definition when talking about workplace health and safety is:

A hazard is any source of potential damage, harm or adverse health effects on something or someone.

Basically, a hazard is the potential for harm or an adverse effect (for example, to people as health effects, to organizations as property or equipment losses, or to the environment).

Sometimes the resulting harm is referred to as the hazard instead of the actual source of the hazard. For example, the disease tuberculosis (TB) might be called a "hazard" by some but, in general, the TB-causing bacteria (Mycobacterium tuberculosis) would be considered the "hazard" or "hazardous biological agent".

Workplace hazards can come from a wide range of sources. General examples include any substance, material, process, practice, etc. that has the ability to cause harm or adverse health effect to a person or property. See Table 1.

Workplace hazards also include practices or conditions that release uncontrolled energy like:

• an object that could fall from a height (potential or gravitational energy),
• a run-away chemical reaction (chemical energy),
• the release of compressed gas or steam (pressure; high temperature),
• entanglement of hair or clothing in rotating equipment (kinetic energy), or
• contact with electrodes of a battery or capacitor (electrical energy).

Please see the OSH Answers on Hazard Identification for more information.

Risk is the chance or probability that a person will be harmed or experience an adverse health effect if exposed to a hazard. It may also apply to situations with property or equipment loss, or harmful effects on the environment.

For example: the risk of developing cancer from smoking cigarettes could be expressed as:

• "cigarette smokers are 12 times (for example) more likely to die of lung cancer than non-smokers", or
• "the number per 100,000 smokers who will develop lung cancer" (actual number depends on factors such as their age and how many years they have been smoking).

These risks are expressed as a probability or likelihood of developing a disease or getting injured, whereas hazard refers to the agent responsible (i.e. smoking).

Factors that influence the degree or likelihood of risk are:

• the nature of the exposure: how much a person is exposed to a hazardous thing or condition (e.g., several times a day or once a year),
• how the person is exposed (e.g., breathing in a vapour, skin contact), and
• the severity of the effect. For example, one substance may cause skin cancer, while another may cause skin irritation. Cancer is a much more serious effect than irritation.

Risk assessment is the process where you:

• Identify hazards and risk factors that have the potential to cause harm (hazard identification).
• Analyze and evaluate the risk associated with that hazard (risk analysis, and risk evaluation).
• Determine appropriate ways to eliminate the hazard, or control the risk when the hazard cannot be eliminated (risk control).

The OSH Answers document on Risk Assessment has details on how to conduct an assessment and establish priorities.

It is common to see the process of identifying hazards and assessing the corresponding risk to be described in various ways, including “hazard assessment”, “hazard and risk assessment”, “all hazards risk assessment”, etc.

Regardless of the terminology used, the critical steps are to make sure the workplace has taken a systematic approach that looks for any hazards (existing or potential), has take appropriate steps to determine the level of risk of these hazards, and then taken measures to control the risk or eliminate the hazard.

Documentation from CCOHS will use the terms “hazard identification ” and “risk assessment ” to describe the process of first looking for hazards, then determining the level of risk from that hazard. Hazard control describes the steps that can be taken to protect workers and the workplace.

A general definition of adverse health effect is "any change in body function or the structures of cells that can lead to disease or health problems".

Adverse health effects include:

• bodily injury,
• disease,
• change in the way the body functions, grows, or develops,
• effects on a developing fetus (teratogenic effects, fetotoxic effects),
• effects on children, grandchildren, etc. (inheritable genetic effects)
• decrease in life span,
• change in mental condition resulting from stress, traumatic experiences, exposure to solvents, and so on, and
• effects on the ability to accommodate additional stress.

Not necessarily. To answer this question, you need to know:

• what hazards are present,
• how a person is exposed (route of exposure, as well as how often and how much exposure occurred),
• what kind of effect could result from the specific exposure a person experienced,
• the risk (or likelihood) that exposure to a hazardous thing or condition would cause an injury, or disease or some incidence causing damage, and
• how severe would the damage, injury or harm (adverse health effect) be from the exposure.

The effects can be acute, meaning that the injury or harm can occur or be felt as soon as a person comes in contact with the hazardous agent (e.g., a splash of acid in a person's eyes). Some responses may be chronic (delayed). For example, exposure to poison ivy may cause red swelling on the skin two to six hours after contact with the plant. On the other hand, longer delays are possible: mesothelioma, a kind of cancer in the lining of the lung cavity, can develop 20 years or more after exposure to asbestos.

Once the hazard is removed or eliminated, the effects may be reversible or irreversible (permanent). For example, a hazard may cause an injury that can heal completely (reversible) or result in an untreatable disease (irreversible).

A common way to classify hazards is by category:

• biological - bacteria, viruses, insects, plants, birds, animals, and humans, etc.,
• chemical - depends on the physical, chemical and toxic properties of the chemical,
• ergonomic - repetitive movements, improper set up of workstation, etc.,
• physical - radiation, magnetic fields, pressure extremes (high pressure or vacuum), noise, etc.,
• psychosocial - stress, violence, etc.,
• safety - slipping/tripping hazards, inappropriate machine guarding, equipment malfunctions or breakdowns.

Document last updated on July 10, 2020

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A person conducting a business or undertaking (PCBU) has a primary duty to ensure the health and safety of workers while they are at work in the business or undertaking and others who may be affected by the carrying out of work, such as visitors. 

The Primary Duty 

The primary duty of care requires PCBUs to ensure so far as is reasonably practicable the:  

• provision and maintenance of a safe work environment 
• provision and maintenance of safe plant and structures  
• provision and maintenance of safe systems of work 
• safe use, handling and storage of plant, structures, and substances 
• provision of accessible and adequate facilities (for example access to washrooms, lockers, and dining areas) 
• provision of any instruction, training, information, and supervision  
• monitoring of workers health and conditions at the workplace and 
• maintenance of any accommodation owned or under their management and control to ensure the health and safety of workers occupying the premises. 

‘Health’ is defined in the model WHS Act as both physical and psychological health. As part of its primary duty a PCBU must manage the risks to a worker’s psychological health, so far as is reasonably practicable.  For further information about psychological health see: 

The workplace environment 

Your duty to provide and maintain a safe working environment includes: 

• the workplace layout 
• lighting 
• work areas 
• floors and surfaces 
• entries and exits 
• fixtures and fittings 
• ventilation.  

You must manage risks with: 

• remote or isolated work (including working from home) 
• airborne contaminants 
• hazardous atmospheres 
• storing flammable or combustible substances 
• falling objects.  

Providing adequate facilities 

You must give workers access to clean and safe facilities and maintain them. Facilities include: 

• toilets 
• drinking water 
• washing and eating facilities 
• first aid equipment and facilities. 

Instruction, training, and supervision 

A PCBU must also: 

• provide adequate training, information and instruction to ensure that each worker is safe from injury and risks to health 
• ensure the provision of first aid equipment and facilities and prepare, maintain, and implement emergency plans 
• manage risks associated with remote or isolated work (including working from home), airborne contaminants, hazardous atmospheres, storage of flammable or combustible substances and falling objects, and  
• comply with requirements regarding the use of personal protective equipment.  

Consulting with workers and representatives 

You must consult with workers who carry out work for the business or undertaking and who are, or are likely to be, directly affected by a health and safety matter. A PCBU must take into account the views of workers consulted and advise those workers of the outcome of the consultation. If the workers are represented by a health and safety representative, the consultation must involve that representative. 

Consulting workers improves decisions about health and safety matters and can help reduce work-related injuries and illness.  

When consulting with workers you must: 

• share information 
• give workers a reasonable opportunity to express their views and contribute to decision-making  
• take those views into account before making decisions on health and safety matters, and 
• advise workers of the outcome of consultations.  

Regular consultation is better than consulting on a case-by-case basis because it allows you to identify and fix potential problems early. 

Your workers are more likely to engage in consultation when their ideas and concerns about health and safety are taken seriously. You should encourage workers to: 

• share their knowledge and experience, and 
• report any work health and safety issues immediately so risks can be managed before an injury occurs. 

For further information see:

Health and Safety Representatives 

A worker may ask for a Health and Safety Representative (HSR) to represent them on work health and safety matters. If workers have an HSR, you must involve them in any consultation on work health and safety matters. 

For further information on HSRs and Health and Safety Committees (HSC) see:

Duties relating to plant, substances or structures used in workplaces 

A PCBU who designs, manufacture, imports or supplies plants, substances or structures used or to be used in a workplace must ensure, so far as is reasonably practicable, that their products are without risks to health and safety when used at a workplace— throughout their entire lifecycle. 

A PCBU who installs, constructs or commissions plant or structures must also ensure, so far as is reasonably practicable, all workplace activity relating to the plant or structure including its decommissioning or dismantling is without risks to health or safety.  

For further information see: 

Managing risks to health and safety 

As a PCBU, you have a duty to ensure the health and safety of workers’ and other persons in the workplace. A PCBU must seek to eliminate risks to health and safety so far as reasonably practicable. If a PCBU cannot eliminate a risk, they must minimise the risks so far as is reasonably practicable. You must identify, assess, and control hazards and risks. 

The model WHS Regulations sets out specific requirements that PCBUs must comply with when managing risks that arise from certain hazards or hazardous work. This includes construction work, hazardous atmospheres or chemicals, asbestos, confined spaces, plant, falls or falling objects, hazardous manual tasks, and diving work. 

For certain risks, the model WHS Regulations provide that where it is not reasonably practicable to eliminate risks to health and safety the PCBU must apply the hierarchy of control measures in minimising risks to health and safety.  These risks include those associated with remote or isolated work, hazardous atmospheres or chemicals, hazardous manual tasks, falls or falling objects, plant, electrical or construction work, hearing loss associated with noise and general diving work.   

The hierarchy of control measures can also be applied in relation to any risk. 

For more information see: 

Managing Specific Workplace Risks 

The model WHS Regulations sets out specific requirements that PCBUs must comply with when managing risks that arise from certain hazards or hazardous work. This includes construction work, hazardous atmospheres or chemicals, asbestos, confined spaces, plant, falls or falling objects, hazardous manual tasks, and diving work. For further information see: 

• The guide to the model WHS Regulations 
• model WHS Regulations   

What is reasonably practicable? 

The term ‘reasonably practicable’ means that which is or was reasonably able to be done at a particular time to ensure health and safety measures are in place, taking into account relevant matters including: 

• the likelihood of the hazard or risk occurring 
• the degree of harm that might result from the hazard or risk 
• knowledge about the hazard or risk, and ways of minimising or eliminating the risk 
• the availability and suitability of ways to eliminate or minimise the risk, and 
• after assessing the extent of the risk and the available ways of eliminating or minimising the risk, the cost associated with available ways of eliminating or minimising the risk, including whether the cost is grossly disproportionate to the risk. 

Applying a risk management process helps to determine what is reasonably practicable. Risk management involves a systematic process to: 

For further information on what is reasonably practicable and risk management see:  

Multiple duty holders – consultation, cooperation, and coordination 

In some circumstances there may be multiple businesses or undertakings involved in the same task or activity (for example suppliers, contractors and building owners). This means there may be multiple PCBUs that owe a duty to workers and other persons.   

If more than one PCBU owes a duty in relation to the same matter, each PCBU retains responsibility and must discharge their duty to the extent to which the PCBU has the capacity to influence and control the matter. A PCBU cannot ‘contract out’ of their responsibility and a duty cannot be transferred to another person. In these situations, each PCBU must, so far as is reasonably practicable, consult, co-operate and co-ordinate activities with all other persons with a duty in relation to the same matter. 

PCBUs should exchange information to find out who is doing what and work together in a cooperative and coordinated way so risks are eliminated or minimised so far as is reasonably practicable. For example, if a PCBU is a tenant in a building, the PCBU will share responsibility for providing a safe physical work environment and facilities with the property manager or building owner and the PCBU should discuss the requirements regarding these matters with them. This would include checking that there are arrangements in place for the proper maintenance of plant such as air-conditioning systems and facilities such as toilets.  

Managing work health and safety risks is more effective if PCBUs involved in the same task or activity exchange health and safety related information. It can also help to improve the efficiency of health and safety measures. 

For further information see:

Supporting information