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34-452: The main aim of the regulations as defined by the 1999 official code of practice was to "establish a framework for ensuring that exposure to ionising radiation arising from work activities, whether man made or natural radiation and from external radiation or internal radiation, is kept as low as reasonably practicable (ALARP) and does not exceed dose limits specified for individuals". The regulations came into force on 1 January 2000, replacing

68-671: A 'tolerable' or 'ALARP' region in between. They were originally developed by the Health and Safety Executive (HSE) to illustrate their framework for the Tolerability of Risk (TOR), which set out the HSE's approach to regulating safety risks. While the ALARP principle applies at all levels of risk under UK health and safety law, the TOR framework captures the concept that some risks are too great to be acceptable, whatever

102-638: A concept often used together with the Swiss cheese model to represent (usually in a bow-tie diagram ) how a threat can escalate to a major accident through the failure of multiple critical barriers. This use has become common especially in the domain of process safety , in particular when applied to oil and gas drilling and production both for illustrative purposes and to support other processes, such as asset integrity management and incident investigation . Several reliability regimes for safety-critical systems exist: Software engineering for safety-critical systems

136-596: A product or developed system. In Australia the Work Health & Safety Act 2011 introduced the term So Far As Is Reasonably Practical (SFAIRP) based on the UK legislation. In some industry sectors the term SFARIP has become the common usage and can be used interchangeably with ALARP, but some people believe that SFAIRP and ALARP are two different legal tests. A two-year legal battle in the European Court of Justice resulted in

170-419: A risk has been reduced as far as reasonably practicable: Another factor is often the cost of assessing the improvement gained in an attempted risk reduction. In extremely complex systems, this can be very high, and could be the limiting factor in practicability of risk reduction, although according to UK HSE guidance, cost alone should never be a justification for taking extra safety risks. Determining that

204-495: A risk has been reduced to ALARP involves an assessment of the risk to be avoided, of the sacrifice (in money, time and trouble) involved in taking measures to avoid that risk, and a comparison of the two. This is a cost–benefit analysis (CBA). A difficulty arising in CBAs is assigning a meaningful and agreed financial value to human life . A CBA exercise, in the context of ALARP, must have a means of assigning financial values to impacts to

238-469: A significant increase in the safety risk for the people or environment involved. Safety-related systems are those that do not have full responsibility for controlling hazards such as loss of life, severe injury or severe environmental damage . The malfunction of a safety-involved system would only be that hazardous in conjunction with the failure of other systems or human error . Some safety organizations provide guidance on safety-related systems, for example

272-424: A standard for which a system is required to be developed under, it forces the designers to stick to the requirements. The avionics industry has succeeded in producing standard methods for producing life-critical avionics software . Similar standards exist for industry, in general, ( IEC 61508 ) and automotive ( ISO 26262 ), medical ( IEC 62304 ) and nuclear ( IEC 61513 ) industries specifically. The standard approach

306-423: Is Reasonably Practicable (SFARP) in this and similar clauses is interpreted as leading to a requirement that risks must be reduced to a level that is As Low As is Reasonably Practicable (ALARP). The key question in determining whether a risk is ALARP is the definition of reasonably practicable . This term has been enshrined in the UK case law since the case of Edwards v. National Coal Board in 1949. The ruling

340-409: Is Reasonably Practicable". The court dismissed the action and ordered the commission to pay the UK's costs. Had the case been upheld, it would have called into question the proportionate approach to safety risk management embodied in the ALARP principle. 'Carrot diagrams' show high (normally unacceptable) risks at the upper/wider end and low (broadly acceptable) risks at the lower/narrower end, with

374-460: Is energy that travels either as electromagnetic waves, or as subatomic particles and can be categorised as either 'ionising' or 'non-ionising radiation'. Ionising radiation occurs naturally but can also be artificially created. Generally people can be exposed to radiation externally from radioactive material or internally by inhaling or ingesting radioactive substances. Exposure to electromagnetic rays such as x-rays and gamma rays can, depending on

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408-522: Is no broad consensus on the precise factor that would be appropriate: the HSE recommends that the bias towards safety "has to be argued in the light of all the circumstances applying to the case and the precautionary approach that these circumstances warrant". The ALARP or ALARA principle is mandated by particular legislation in some countries outside the UK, including Australia, the Netherlands and Norway. Where

442-491: Is particularly difficult. There are three aspects which can be applied to aid the engineering software for life-critical systems. First is process engineering and management. Secondly, selecting the appropriate tools and environment for the system. This allows the system developer to effectively test the system by emulation and observe its effectiveness. Thirdly, address any legal and regulatory requirements, such as Federal Aviation Administration requirements for aviation. By setting

476-459: Is reasonably practicable ( SFAIRP ). In the US, ALARA is used in the regulation of radiation risks. For a risk to be ALARP, it must be possible to demonstrate that the cost involved in reducing the risk further would be grossly disproportionate to the benefit gained. The ALARP principle arises from the fact that infinite time, effort and money could be spent in the attempt of reducing a risk to zero; not

510-420: Is to carefully code, inspect, document, test, verify and analyze the system. Another approach is to certify a production system, a compiler , and then generate the system's code from specifications. Another approach uses formal methods to generate proofs that the code meets requirements. All of these approaches improve the software quality in safety-critical systems by testing or eliminating manual steps in

544-559: The Health and Safety Executive in the United Kingdom . Risks of this sort are usually managed with the methods and tools of safety engineering . A safety-critical system is designed to lose less than one life per billion (10 ) hours of operation. Typical design methods include probabilistic risk assessment , a method that combines failure mode and effects analysis (FMEA) with fault tree analysis . Safety-critical systems are increasingly computer -based. Safety-critical systems are

578-635: The Health and Safety Executive (HSE). They form the legal basis for ionising radiation protection in the United Kingdom (UK), although work with ionising radiation is also controlled in the UK through other statutory instruments such as the Nuclear Installations Act 1965 and the Radioactive Substances Act 1993 . The IRR99 make legal requirements including prior authorisation of the use of particle accelerators and x-ray machines,

612-563: The 'Ionising Radiations Regulations 1985'. They effectively implement the majority of the European Basic Safety Standards Directive '96/29/Euratom' under the auspices of the Health and Safety at Work etc. Act 1974 . This European Directive is in turn a reflection of the recommendations of the International Commission on Radiological Protection . The regulations are aimed at employers and are enforced by

646-539: The 2017 regulations are summarised in the approved code of practice. These include: The introduction of the Ionising Radiation (Medical Exposure) Regulations 2017 (IRMER17, the legislation that governs medical exposures in the UK) amended IRR17 to remove the regulation concerning medical equipment. These requirements are now under IRMER17. The dose limit to the lens of the eye has been reduced based on ICRP recommendation,

680-460: The ALARP principle is used, it may not have the same implications as in the UK, as "reasonably practicable" may be interpreted according to the local culture, without introducing the concept of gross disproportionality. The term ALARA, or "as low as reasonably achievable" is used interchangeably in the United States of America. It is used in the field of radiation protection . Its application in

714-561: The SFAIRP principle being upheld on 18 January 2007. The European Commission had claimed that the SFAIRP wording in the Health & Safety at Work Act did not fully implement the requirements of the Framework Directive . The Directive gives employers an absolute duty "to ensure the safety and health of workers in every aspect related to the work", whereas the Act qualifies the duty "So Far As

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748-619: The Tolerability of Risk framework rather than the ALARP principle itself, and can be misinterpreted as meaning either that ALARP legally applies only in the tolerable region, or that risks in tolerable region are automatically ALARP. Safety-critical A safety-critical system or life-critical system is a system whose failure or malfunction may result in one (or more) of the following outcomes: A safety-related system (or sometimes safety-involved system ) comprises everything (hardware, software, and human aspects) needed to perform one or more safety functions, in which failure would cause

782-522: The additional risk control will not provide additional support for the system, such as an additional alarm when a previous alarm is functioning. The second states that a risk control system does not have to be implemented if there is a more effective risk control that can not be simultaneously executed due to various scenarios such as spatial boundaries. By implementing this new standard of risk mitigation, companies must demonstrate that they have considered and implemented all necessary means of addressing risk of

816-537: The appointment of radiation protection supervisors (RPS) and advisers (RPA) , control and restriction of exposure to ionising radiation (including dose limits), and a requirement for local rules. Local rules including the designation of controlled areas , defined as places where "special procedures are needed to restrict significant exposure". In 2013 the European Union adopted directive 2013/59/Euratom which requires updated Ionising Radiations Regulations to implement

850-610: The benefit; while others are so low as to be insignificant. The HSE, as regulators, would not usually require further action to reduce these broadly acceptable risks unless reasonably practicable measures were available, although they would still take into account that duty holders must reduce risks wherever it is reasonably practicable to do so. Between the two extremes, risks can be tolerated in order to secure benefits, so long as they have been risk assessed and are kept ALARP. Carrot diagrams are sometimes known as 'ALARP Triangles'. However, this can be misleading because they illustrate

884-479: The directive in UK law by 2018. Changes include reduced eye dose limits as a result of updated ICRP recommendations. The regulations impose duties on employers to protect employees and anyone else from radiation arising from work with radioactive substances and other forms of ionising radiation. In the United Kingdom the Health and Safety Executive is one of a number of public bodies which regulates workplaces which could expose workers to radiation. Radiation itself

918-419: The environment, physical assets, production stoppage, company reputation, etc., which also presents significant challenges to the analyst. The term ALARP arises from UK legislation, particularly the Health and Safety at Work etc. Act 1974 , which requires "Provision and maintenance of plant and systems of work that are, so far as is reasonably practicable, safe and without risks to health". The phrase So Far As

952-469: The fact that reducing the risk in half would require a finite time, effort and money. It should not be understood as simply a quantitative measure of benefit against detriment. It is more a best common practice of judgement of the balance of risk and societal benefit. In this context, risk is the combination of the frequency (likelihood) and the consequence of a specified hazardous event. Several factors are likely to be considered when deciding whether or not

986-422: The intent of the consumer and effectiveness of the product rather than capital gain of the corporation. Risks previously deemed 'negligible' may be ignored under the old standard but must be taken into account and included in risk analysis under the newer AFAP-based standard. Under AFAP standards there are two defined justifications for the lack of implementation of risk-preventative measures. The first indicates that

1020-410: The new limits are now as follows ALARP As low as reasonably practicable ( ALARP ), or as low as reasonably achievable ( ALARA ), is a principle in the regulation and management of safety-critical and safety-involved systems. The principle is that the residual risk shall be reduced as far as reasonably practicable. In UK and NZ Health and safety law , it is equivalent to so far as

1054-489: The regulation of radiation risk in some areas has been challenged. Health Canada 's Medical Devices Directorate is transitioning from the ALARP standard to AFAP ("As Far As Possible") in the regulation of risk of medical devices. The ALARP concept can be interpreted to promote financial consideration in higher regard than of the requirements of safety and performance of medical devices . Contradicting this approach, AFAP requires that all ventures of safety must be addressed in

Ionising Radiations Regulations - Misplaced Pages Continue

1088-537: The sun or from sunbeds which could lead to skin cancer . The regulations are split into seven parts containing 41 regulations. under the following sections. In addition to requiring that radiation employers ensure that doses are kept as low as reasonably practicable (ALARP), the IRR99 also defines dose limits for certain classes of person. Dose limits do not apply to people undergoing a medical exposure or to those acting as "comforters and carers" to such. The main changes in

1122-443: The time exposed, cause sterility, genetic defects, premature ageing and death. Non-ionising radiation is the terms used to describe the part of the electromagnetic spectrum covering 'Optical radiation', such as ultraviolet light and 'electromagnetic fields' such as microwaves and radio frequencies. Health risks caused by exposure to this type of radiation will often be as a result of too much exposure to ultraviolet light either from

1156-419: Was that the risk must be significant in relation to the sacrifice (in terms of money, time or trouble) required to avert it: risks must be averted unless there is a gross disproportion between the costs and benefits of doing so. Including gross disproportion means that an ALARP judgement in the UK is not a simple cost benefit analysis, but is weighted to favour carrying out the safety improvement. However, there

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