Reasonably foreseeable worst case consequence Likelihood3 of hazard event	Minor Superficial injury; or slight and temporary health effect	Moderate Significant injury or illness1; or temporary minor disability	Major Serious injury or illness2; or significant or permanent disability	Critical Fatal injury or illness; or substantial and permanent disability	Catastrophic Fatal injury or illness for multiple persons
Likely High probability, 1 in 10 chance or higher, once in two weeks or longer for activities on a daily basis	medium risk	high risk	high risk	high risk	high risk
Possible Significant probability, 1 in 100 chance or higher, once in six months or longer for activities on a daily basis	low risk	medium risk	high risk	high risk	high risk
Unlikely Low probability, 1 in 1,000 chance or higher, once in four years or longer for activities on a daily basis	low risk	low risk	medium risk	high risk	high risk
Rare Very low probability, 1 in 10,000 chance or higher, once in a decade or longer for activities on a daily basis	low risk	low risk	low risk	medium risk	high risk
Almost never Extremely low probability, less than 1 in 100,000 chance, once in a century or longer for activities on a daily basis	low risk	low risk	low risk	low risk	medium risk

 

High risk: Requires controls to reduce risk before activity/task can commence (or continue).

Medium risk: Requires controls to reduce risk as much and as soon as is reasonably practicable.

Low risk: All risk should be reduced to this tolerable level, so far as is reasonably practicable.

¹ ‘Significant injury’ could include, for example, laceration, burn, concussion, serious sprain, minor fracture, etc. ‘Significant illness’ could include, for example, dermatitis, minor work-related musculoskeletal conditions, partial hearing loss, etc.

² ‘Serious injury’ could include fracture or dislocation (other than digits), amputation, loss of sight, penetration or burn to eye, electric shock, asphyxia, or any injury leading to unconsciousness or requiring resuscitation or admittance to hospital for more than twenty-four hours. ‘Serious illness’ could include, for example, requiring medical treatment after chemical, biological or radiological exposure, severe debilitating musculoskeletal conditions, severe dermatitis, asthma, etc.

³ For likelihoods in between the listed values, use the higher likelihood to estimate risk. These probability definitions are only a guide.

 

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…On to Example Risk Assessment Form: Cover Page/Declaration.