Hazard, Risk Assessment, and Determining Control

Risk assessment are a legal requirement for any hazardous work activity. A Risk Assessment should be carried out – “ in a systematic way – using a common sense approach.” Risk assessment involves a number of stages. When carrying out a Risk Assessment you should follow the basic steps:
1.    List  the work tasks/activities in the area
2.    Identify the risks arising from the work tasks
3.    Estimate the size of risk
4.    Evaluate the level of risk (taking into account existing control measures)
5.    Record the assessment ( this is a legal requirement in most countries )
6.    Review the assessment to ensure it remains valid.
The following explanations are basic to the understanding of risk assessment process.

Hazard
A hazard may be defined as,” A physical situation with a potential for human injury, damage to property, damage to environment or some combination of these”, or, “ An unsafe condition or unsafe practice with a potential to cause damage, ill-health, injury or other loss.”
i.e. ‘An accident waiting to happen.’
A hazard may be: rotating plant, flammable gas, toxic gas, workshop equipment, confined spaces, energy sources etc.

Risk
Risk is a combination of the potential accident SEVERITY (death, serious injury, cuts, etc.) and the LIKELIHOOD of that accident occurring (very unlikely, probable, almost certain, etc.)
Consider a rotating flywheel. This has the potential to cause death or severe injury (hazard severity). However, the risk depends on the likelihood of a person getting entangled. If a good machine guard is in place the flywheel will be a ‘low  risk’ hazard, if no guard is in place it will be a very ‘high risk’.

Tolerable Risk
The objective should always be to eliminate risk from the workplace. However, where a risk cannot be eliminated, e.g. by a change in work practice, a point has to be reached where the risk has been reduced to a TOLERABLE level. Many organizations will aim to reduce a risk to As Low As is Reasonably Practicable – ‘ALARP’.

Risk Assessment
Once we have identified a range of hazards, we must be able to determine whether they are, ‘low risk’ and therefore not worth considering further, ‘high risk’ requiring immediate action, or somewhere in between.
By allocating a severity factor and likelihood factor to each risk that arises from a hazard, we can compare the magnitude of the various risks by multiplying the severity and likelihood ratings:

 RISK = SEVERITY X LIKELIHOOD

A common approach is to use a rating scale of 1 to 5 where 1 represents a low level of likelihood and severity. Ratings of 5 would be high. This provides a risk scale of 1 to 25 ( see below). The use of numbers is not an exact science. Assessment of likelihood and severity are subjective and should be seen as a useful tool. Company may give guidance on how to use the ratings to try and achieve consistency.

The method as outlined is suitable for assessing ‘day to day’ risks. Hazards that generate very high risks, especially if they have a potential for fatalities, require a more detailed risk assessment. In such cases, specialist advice should be sought.