residual risk

[savitha kandasamy]

Dear Members,

I couldn't able to understand about residual risk. Kindly provide an example to understand about residual risk.

Regards,
saitha

[Peter]

Dear Members,

I couldn't able to understand about residual risk. Kindly provide an example to understand about residual risk.

Regards,
saitha

If you throw a random person in the swimming pool without warning, there is a risk that they will drown. If you attempt to mitigate that by selecting a person who has had swimming lessons, the risk will be lower because at least you know they should be able to swim. If you warn the person they are about to be thrown in the water, the risk falls further because they are prepared for what is about to happen to them. You could mitigate it further by providing a life guard in case they still get into trouble and a paramedic team to lessen the severity. Despite taking all of the reasonable mitigation measures, there is the residual risk that something highly unlikely will cause them to drown. Residual risk is the element that is left when you have put in place a set of measures.

It may be that the residual risk is tolerable, in which case you carry on. It may be that it is not and you have to look for further mitigations or alternative ways of working.

[jaheen100]

Huh how you would apply it to problem solving strategies?? any ideas?

[Peter]

Huh how you would apply it to problem solving strategies?? any ideas?

You need to understand what the risks are and what levels you are prepared to tolerate. There are many formal methods for hazard identification.

[roddy]

Dear Members,

I couldn't able to understand about residual risk. Kindly provide an example to understand about residual risk.

Regards,
saitha

Hi savitha kandasamy

To understand Residual Risk it is useful to look at the definition of ALARP. ALARP means As Low As is Reasonable Practicable, and its full definition, as provided in Ellis’s Engineering Encyclopaedia is ‘a description of the residual risk that is acceptable acknowledging that there will always be some small risk remaining irrespective of the funds expended in trying to eliminate it’.

A Risk Assessment is used to identify hazards, to estimate the risk associated with them, and, most importantly, to evaluate whether the risk is acceptable.

The Risk Assessment process on Irish Railways is the Qualitative Risk Assessment. It relies on domain expert judgment and past experience. The risks associated with the identified hazards are ranked using the Qualitative Risk Matrix; see Engineering Safety Management ‘The Yellow Book’ Table 15-1.

During the risk assessment each hazard, with the current safety measures considered, is given a likelihood and severity rating, with the risk ranking being the product of the two. For example a hazard with an ‘Improbable’ (2) likelihood and a ‘Marginal’ (2) severity will have a negligible (4) risk [2 x 2].

The Risk Rankings on the Risk Matrix are categorised as either:

• Negligible – these are considered low enough, and the identification of further safety measures to drive the risk lower is not required.
• Tolerable – these are considered acceptable, but consideration should be given to providing additional safety measures to reduce the risk, if practicable (see the definition of ALARP).
• Undesirable – these require the identification of additional safety measures to reduce the risk, and, if not possible, demonstration of ALARP is required.
• Intolerable – these are not acceptable, and, either the hazard must be eliminated or safety measures found to reduce the risk.

If the risk associated with a hazard is not Negligible, additional safety measures may be identified, which will result in a Residual Risk. The additional safety measures will usually have the effect of reducing the likelihood associated with a particular hazard. The safety measures adopted to reduce risk will become known as the Safety Requirements.

Please see the attached files for an example.

Rod