ALARP good practices

A key feature of the new proposals therefore was to link principles of good practice with compliance with the WEL. In so doing the proposed regulations would require employers to both apply principles of good practice and not exceed the WEL. In addition specific requirements to reduce the amounts of carcinogens in workplace air to as low as is reasonably practicable (ALARP) were to be specified. 

Requirements 1 to 7 can be met by the application of either qualitative or quantitative hazard and risk analysis techniques as per part 5 of the Standard. The example to date has applied a quantitative analysis employing a number of techniques. In terms of qualitative assessment, an "unlikely failure but with "catastrophic outcome represents an extreme risk necessitating "necessary risk reduction and application of ALARP (as low as reasonably practicable), good practice and continuous risk reduction principles... 

Within the PSLG Final Report, particular emphasis is given to overfill prevention as this is the primary means by which this major accident hazard can be prevented. In assessing what overfill prevention measures are required to reduce the risk to the environment to ALARP, the existing capacity of the bund and the tank level it was based on must be taken into account to determine the potential environmental consequences, eg whether the spillage is likely to be retained by the secondary containment system. If the overfill prevention system and the primary containment measures as a whole are in accordance with good practice, the risk to the environment is reduced. 

ALARP (Relevant good practice + risk reduction until gross... 

This review underpins the choice of codes and standards for the safety classes that are defined for the AP 1000 in the UK, and demonstrates, in support of the ALARP assessment in the PCSR, that relevant good practice has been used in plant design. 

This ALARP assessment of the design of the APIOOO begins by exploring how the various standards defining current good practice have been applied to the design of the APIOOO. These standards are considered over three levels ... 

Safe and Simple the Genesis of the APIOOO Design has described the evolution of the APIOOO design, identifying input from utilities and relevant good practice in its development. This report has been a key reference in the demonstration that risk associated with operation of the APIOOO is as low as reasonably practicable (ALARP). 

Having established a SIL target it is insufficient merely to assess that the design will meet the Maximum Tolerable Risk target. It is necessary to establish whether further improvements are justified and thus the principle of ALARP (as low as reasonably practicable) is called for as good practice. In the UK this is also arguably necessary in order to meet safety legislation ( all that is reasonably practicable is called for in the Health Safety at Work Act 1974). 

The concept of ALARP helps with respect to the economic considerations necessary in risk decision making. A good and easily understood definition of ALARP may be found in the draft of MIL-STD-882E, the Department of Defense Standard Practice for System Safety ... 

An organisation responsible for managing safety risk has to determine whether risk is already as low as reasonably practicable conversely, it has to determine whether potential risk reductions are reasonably practicable to implement. This decision can be made in different ways to match different circumstances. For example, compliance with an accepted code of practice is sometimes regarded as a good indicator of risk being ALARP or it may be that professional judgement is the best means of making a decision. 

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