Safety Case ALARP

This system has proven to provide adequate levels of safety in the Gulf of Mexico and other similar areas where it is possible to abandon the location during a catastrophic event. In the North Sea where harsh environmental conditions exist, a different approach to safety has evolved which is based on developing a Safety Case and calculating an Individual Risk Rate (IRR) to show that the risk to any individual working in the facility is As Low As Reasonably Practicable (ALARP). 

A Safety Case is a narrative that literally makes the case that an adequate level of safety has been reached for an installation. It requires looking at all potential hazards which could lead to a loss of the installation, a loss of life, or a major pollution event. A risk analysis is performed on each hazard evaluating the probability of the event occurring and describing the magnitude of the consequences. A discussion is then given of the measure undertaken to lower the probability of occurrence or to mitigate the consequences and a case is made that the risk for the installation meets the ALARP safety criteria. 

The regulatory environment is changing in Victoria with introduction from March 2000 of the Major Hazard Facilities Regulations, based on the Seveso II Directives. These are expected to flow on to the other states considered in this chapter. The key requirement of these regulations is the preparation of a Safety Case, which must demonstrate, among other requirements, that the risk from the new plant has been reduced to as low as is reasonably practicable - ALARP . The plants will incorporate a number of design features intended to reduce the risk from the facilities and demonstrate compliance with this criterion. 

It is rarely possible to completely mitigate a risk other than by somehow taking action to avoid the associated hazard in the first place. Instead, risks need to be reduced so that they become As Low As Reasonably Practical (ALARP). Remedial project actions should be specifically documented — this is sometimes referred to as the Safety Case. Remedial actions may employ hazard avoidance strategies, introduce hazard tolerant design feamres, or apply specihc project management controls, or a combination. Further information on risk management for medical devices can be found in ISO 14971. ... 

Finally ALARP introdnces a basis for justifying risks, to make a case for them being present but tolerable. To justify something in this way reqnires carefnl analysis and logic set out as an evidence-based argument. The vehicle for this jnstifica-tion is a document known as a safety case. 

The notion of reducing risk to as low as reasonably practicable or ALARP has been widely adopted in some countries. This measure creates the necessarily flexibility to allow the justification of residual risk using a safety case. 

Realistically, it has to be concluded that the term ALARP really does not provide much help to risk management professionals and facility managers in defining what levels of risk are acceptable. It may be for this reason that the U.K. HSE chose in the year 2006 to minimize its emphasis to do with ALARP requirements from the Safety Case Regime for offshore facilities. Other major companies have also elected to move away from ALARP toward a continuous risk reduction model (Broadribb, 2008). 

The safety case concept requires that operators demonstrate that the systems and processes they have adopted ensure that their facility is sufficiently safe for all those people who are possibly impacted by their activities (workers and contractors at their facility, passengers and customers, people who live and work in surrounding areas). Most safety case regulations require the demonstration to take the general form of showing that risk is as low as reasonably practicable, or ALARP (or that risk has been reduced so far as practicable - SFAP). Clearly, safety cases are an example of the broad trend towards risk-based regulation (Hood et al. 2004). 

The ALARP (As low as Reasonably Practicable) principle is the basis of the UK Safety Case Regulations, and requires every employer to adopt safety measures unless the cost is grossly disproportionate to the risk reduction . 

The author is aware of at least one equipment safety case intending to use this method for ALARP Justifications in the future, the intent has already been independently endorsed. 

Petroleum Institute (API) developed their Recommended Practice 75 (RP 75), which recommended that offshore facilities develop a Safety and Environmental Management Program (SEMP). Like a safety case, RP 75 is mostly nonprescrip-tive. However, it makes extensive reference to industry standards (mostly from the American Petroleum Institute), and so it is perceived as being considerably more prescriptive then the safety case approach. Nor does RP 75 require that a formal assessment of acceptable risk (ALARP) be determined. 

It may be for reasons such as these that the United Kingdom Health and Safety Executive (HSE) in 2006 decided to minimize its emphasis of ALARP requirements from the Safety Case Regime for offshore facilities. Some... 

Management has to decide if the calculated level of risk is acceptable, and, if it is not, what actions need to be taken to reduce it. Some Safety Management Systems—in particular many Safety Cases—are built around the concept of a numerical value for an ALARP (As Low as Reasonably Practicable) value, as already discussed. If the risk lies above or below the predetermined ALARP value then corrective actions must be taken. 

A Safety Case does not have to be quantified. Indeed, only half the European countries stipulate the use of Quantified Risk Analysis (QRA) in their Safety Case legislation (Rasche 2001). Nevertheless, it is difficult to demonstrate that risks have been reduced to the target ALARP threshold without some type of quantification. 

Some Safety Case reports contain an as low as reasonably practicable (ALARP) demonstration section that shows how the identified major hazards have been managed such that the associated level of risk is acceptable. The vexed topics of ALARP and acceptable risk are discussed in Chapter 1. 

It all started with the 1988 Piper Alpha North Sea Oil Platform accident, killing 167 people and causing over 3.6B in insurance claims. The subsequent Cullen Inquiry led to the development and promulgation in 1992 of the Offshore Installations (Safety Case) 1992, later updated in 2005 (United Kingdom, 2005). Now many industries (especially in the United Kingdom, Australia, New Zealand, and Europe), in addition to petroleum, use the safety case process including aviation, nuclear, rail, and military hardware. See Chapter 2 for more on ALARP. 

Central to the safety case is the hazard control and risk manag ent process, ensuring that risks are well managed. ALARP is used to determine how far you should go to control the hazard. The safety case process is very thorough and highly labor intensive and, if you are not careful, could become overly bureaucratic. It is just a snapshot in time of the safety of the system, so that means that it must be maintained to still be relevant. This is where bureauCTacy can take over if not careful. 

A documented safety case needs to be produced to present the claims, arguments, and evidence that the plant or facility is safe to undertake its scope of operation throughout its required life. A safety case is the totality of documented information and arguments that substantiates the safety of the plant, activity, operation, or modification in question. It provides a written demonstration that relevant standards have been met and that risks have been reduced ALARP. The safety case for the plant should be a living document, which is subject to review, change, and amendment as time proceeds. 

Current practice in the UK demands demonstration of corrqiliance with the As Low As Reasonably Practicable (ALARP) principle for arty imdertaking. This demonstration is typically stmctnred in the form of a Safety Case. 

Axle counter application risk models were developed to support the derivation of Safety Cases for individual axle counter installation projects. In accordance with the UK safety case regime, each project will have to prove that the technological and procedural solution accepted for the project is the As Low As Reasonably Practicable (ALARP) solution. 

The Axle Counter Concept Safety Case does not attempt to show that risks associated with axle counters are ALARP in an absolute sense. It does show that the risks associated with axle counters can be made as low, or lower than, those associated with track circuits. 

It provides a framework so that individual application safety cases can demonstrate that the type of axle counter system that is being commissioned on a particular project reduces the risks to ALARP (relative... 

Application specific issues cannot be addressed at the concept level. To demonstrate ALARP, it is necessary to consider the specific application in conjunction with the Concept Safety Case, as the latter caimot deal with reasonable practicality in all situations and combinations of applications. 

Development of the methodology supporting the generic activities of safety risk analysis and management process for any system would bring benefits to the industry. Moreover, since the current practice in the UK is that demonstration of conpliance with the ALARP principle is structured in the form of a Safety Case, the process also needs to support the development of the Safety Case. 

The conclusion of the Safety justification was that a set of restrictions, dependencies and other safety measures had been identified which enabled the train operations, associated with V2.01 testing, to be performed at a level of risk which is tolerable and ALARP. This Safety justification can thus be seen a subset of the reasoning model that is the System Safety Case for VLUP. 

The approach described above, although similar to ALARP, rather than considering the necessity of adopting measures to directly decrease risk, instead considers measures intended to increase the confidence that is achieved. As such the framework could be considered to help estabhsh a claimed risk position in the software safety case that is ACARP (As Confident As Reasonably Practicable). 

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