Arshad Ahmad

Transcription

1 Arshad Ahmad 1 arshad@utm.my innovative entrepreneurial global 1

2 Risk to People Risk Matrix Risk Acceptance Criteria Voluntary Vs Involuntary Risks innovative entrepreneurial global 2

3 A single death is a tragedy, a million deaths is a statistic. Joseph Stalin innovative entrepreneurial global 3

4 In the context of risk assessment, an indicator is a quantity that provides information about the level of risk Risk indicator A parameter that is estimated based on risk analysis models and by using generic and other available data. A risk indicator presents our knowledge and belief about a specific of the risk of a future activity or a future system operation Safety performance indicator A parameter that is estimated based on experience data from a specific installation or an activity. A risk performance indicator therefore tells us what has happened Risk indicators are used to assess (prospective) risk, whereas safety performance indicators are used mainly for monitoring purposes innovative entrepreneurial 4 global 4

5 Individual risk is the risk that an individual person is exposed to during a specific time period (usually, one year). Individual risk does not depend on the number of people who are exposed to the hazard. Group risk is the risk experienced by a group of people. The group risk is a combination of individual risk levels and the number of people at risk, that is, the population being exposed. innovative entrepreneurial global 5

6 Individual risk is the risk that an individual person is exposed to during a specific time period (usually, one year). Individual risk is usually addressed in terms of a hypothetical or statistical person, who is an individual with some defined, fixed relationship to the hazard. Individual risk does not depend on the number of people who are exposed to the hazard. Individual risk: The frequency with which an individual may be expected to sustain a given level of harm from the realization of specified hazards (IChemE, 1992) innovative entrepreneurial global 6

7 IRPA i = Pr(individual is killed due to hazards i during one year's exposure) IRPA i may be estimated based on the number of fatalities observed in a specified time period for a specific group of individuals who have been exposed to the same hazards i, IRPA i = Observed no. of fatallities due to hazards i total no. of person- years exposed innovative entrepreneurial global 7

8 Federal traffic officer chief, SAC Mohd Fuad Abdul Latiff said there were 5138 deaths this year compared to 5357 during the same period last year. (The Star, Tuesday, Oct 2014) IRPA i = = x 10-4 fatalities per person per year This means that in a group of people on average almost 2 person got killed in 2014 in Malaysia. This is an individual risk. NOTE: This is an average figure for Malaysia. A much higher value is expected in peninsular Malaysia This number is the average value for a person at random, among all inhabitants of Malaysia innovative entrepreneurial global 8

9 Consider a person who is traveling by air between two cities n times a year. The frequency of accidents on this stretch has been estimated to be A. The IRPA for this activity is then IRPA i = λ. Pr(the person on board of flight). Pr (the person killed the person is on board) innovative entrepreneurial global 9

10 Localized individual risk (LIRA): The probability that an average unprotected person, permanently present at a specified location, is killed in a period of one year due to an accident at a hazardous installation (e.g., see Jonkman et al., 2003) LIRA is also called individual risk (LSIR) and Individual risk index, and is used mainly for land-use planning. LIRA for an individual event LIRA i (x,y) = λ i. Pr (fatality at (x,y) A i ) for i = 1,2,...,n The total LIRA at location (x,y) due to the hazardous installation LIRA (x,y) = λ i. Pr (fatality at (x,y) A i ) LIRA (x,y) = n n i=1 LIRA may also consider the proportion of time a the individual is actually present at location (x,y) i=1 λ i. Pr (fatality at (x,y) A i ). a innovative entrepreneurial global 10

11 1 x x 10-5 Hazardous Installation 1 x 10-6 Criteria for Land Use in Malaysia (LSIR) Industrial receptors < 1 x 10-5 Residential receptors < 1 x innovative entrepreneurial global 11

12 Exposure Type Hospitals, schools, child-care facilities, nursing homes Residential & places of continuous occupation (hotels/resorts) Commercial developments, including offices, retail centers, ware-houses with showrooms, restaurants and entertainment centers. Sporting complexes and active open space areas Risk Level Less than 5 x 10-7 Less than I x 10-6 Less than 5 x 10-6 Less than I x 10-5 Industrial sites Less than 5 x innovative entrepreneurial global 12

13 If a person dies at age t due to an accident, the RLE, is defined as RLE t =t 0 - t where to denotes the mean life length of a randomly chosen person of the same age as the person killed, who has survived up to age t. Cause Days Heart Disease 2100 Cancer 980 Stroke 520 Motor Vehicle Accidents 207 Accidents at home 95 Average jobs accidents 74 Drowning 41 Accidents to pedestrian 35 Source: Fischoff et al. (1981) innovative entrepreneurial global 13

14 A lost-time injury (LTI) is an injury that prevents an employee from returning to work for at least one full shift. The frequency of LTis is often used as a safety performance indicator and is defined as LTIF =! no!of!lti no!of!hours!.! innovative entrepreneurial global 14

15 Lost Workdays Frequency. The LTIF does not weight the seriousness of the injury, so a fatal accident has the same effect on the LTIF as does a broken finger. The seriousness of an LTI may be measured by the number of workdays lost due to the LTI, and the lost workdays frequency, LWF, may alternatively be used as a safety performance indicator. The LWF* is defined as no!of!loss!workdays!due!to!lti!! LWF =! no!of!hours!worked!.! innovative entrepreneurial global 15

16 Bird and Germain (1986) reports 1 serious or disabling injury 10 minor injuries 30 property damage accidents (all types) 600 incidents with no reported injury or damage (near misses) innovative entrepreneurial global 16

17 Potential loss of life (PLL): The PLL is the expected number of fatalities within a specified population (or within a specified area A) per annum. PLL A =! PLL for a Specified Population. Assume that all the members of a population have the same individual risk per annum, IRPA. Let n denote the number of members of the population. The PLL is then determined by! PLL = n.irpa A PLL in Norway (example) A IRPA(x, y)m(x, y)dxdy Type of Occupation Agriculture Transport & Communication Construction Health & Social Services PLL innovative entrepreneurial global 17

18 Fatal accident rate (FAR): The expected number of fatalities in a defined population per I00 million hours of exposure. FAR =! Experienced FAR* expected!no!of!fatalities no!of!hours!exposed!to!risk!.!108 FAR * =! observed!no!of!fatalities no!of!hours!exposed!to!risk!.!108 innovative entrepreneurial global 18

19 Experienced FAR (Nordic Country: ) Type of Occupation Agriculture, forestry, fishing, and hunting Industry, manufacturing Building and construction Trade, restaurant, and hotel Transport, post, and telecommunication Banking and insurance Private and public services, defense, etc. FAR (Fatalities per 10 8 working hours) innovative entrepreneurial global 19

20 Experienced FAR (UK: ) Hambly (1992) Type of Occupation Factory Work (average) Construction (Average) Construction(high rise erector) Manufacturing (all) Oil & gas extraction Travel by car Travel by air (fixed wing) Travel by helicopter Rock climbing while on rock face) FAR (Fatalities per 10 8 working hours) I innovative entrepreneurial global 20

21 Group risk is the risk experienced by a group of people. When common citizens are exposed, the group risk is often called societal risk. The group risk is a combination of individual risk levels and the number of people at risk, that is, the population being exposed. Societal risk: The relationship between frequency and the number of people suffering from a specified level of harm in a given population from the realization of specific hazards (IChemE, 1992). innovative entrepreneurial global 21

22 Industry Sector Annual Risk Annual Risk Fatalities to employees Fatalities to self-employed Mining and quarrying of energy producing materials Construction Extractive and utility supply industries Agriculture, hunting, forestry, and fishing (not sea fishing) Manufacture of basic metals and fabricated metal products Manufacturing industry Manufacture of electrical and optical equipment Service industry 1 in in in in in in in in in in (HSE, 2001, Reducing Risks, Protecting People: HSE's Decision-Making Process ) innovative entrepreneurial global 22

23 The FN curve may be used for at least three purposes: To show the historical record of accidents To depict the results of quantitative risk assessments To display criteria for judging the tolerability or acceptability of outputs from quantitative risk assessments Frequency of "excedance," meaning that F(n) denotes the frequency of accidents where the consequence is n or more fatalities.! F(n)= λ = λ.pr(n n) [N n] innovative entrepreneurial global 23

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25 Risk = Likelihood x Severity Likelihood of Occurrence - Frequency - Probability Severity of the Consequence - Fatality, loss, illness, etc. - Impact innovative entrepreneurial 25 global 25

26 A risk matrix is a tabular illustration of the frequency and severity of hazardous events or accident scenarios. The risk matrix may be used to rank hazardous events according to their Significance, to screen out insignificant events, or to evaluate the need for risk reduction for each event (e.g., see HSE, 2001). innovative entrepreneurial global 26

27 Description Category Environmental, Safety and Health Result Criteria Catastrophic I Death, permanent total disability Loss of exceeding $1M Irreversible severe environmental damage that violates law or regulation Critical II Permanent partial disability, injuries or occupational illness that may result in hospitalization of at least 3 personnel Loss exceeding $200K but less than $1M Reversible environmental damage causing a violation of law or regulation Marginal III Injury or occupational illness resulting in one or more loss of workdays Loss exceeding $10K but less than $200K Mitigatible environmental damage without violation of law or regulation where restoration activities can be accomplished Negligible IV Injury or illness not resulting in a lost work day Loss exceeding $2K but less than $10K Minimal environmental damage not violating law or regulation Source: MIL-STD-882D 27 innovative entrepreneurial global 27

28 Description Level Specific Individual Item Fleet or Inventory Frequent A Likely to occur than 10-1 in that life Continuously experienced Probable B Will occur several times in the life on an item, with probability of occurrence less than 10-2 but greater than 10-3 in that life Will occur frequently Occasional C Likely to occur some time in the life of an item, with a probability of occurrence less than 10-2 but greater than 10-3 in that life Remote D Unlikely but possible to occur in the life of an item with a probability of occurrence less than 10-3 but greater than 10-6 in that life Improbable E So unlikely, it can be assumed occurrence may not be experienced, with a probability of occurrence less than 10-6 Will occur several times Unlikely but can be reasonably expected to occur Unlikely but possible Source: MIL-STD-882D 28 innovative entrepreneurial global 28

29 Description Severity Category SEVERITY CATEGORIES Mishap Result Criteria Catastrophic 1 Critical 2 Marginal 3 Could result in one or more of the following: death, permanent total disability, irreversible significant environmental impact, or monetary loss equal to or exceeding $10M. Could result in one or more of the following: permanent partial disability,injuries or occupational illness that may result in hospitalization of at least three personnel, reversible significant environmental impact, or monetary loss equal to or exceeding $1M but less than $10M. Could result in one or more of the following: injury or occupational illness resulting in one or more lost work day(s), reversible moderate environmental impact, or monetary loss equal to or exceeding $100K but less than $1M. Negligible 4 Could result in one or more of the following: injury or occupational illness not resulting in a lost work day, minimal environmental impact, or monetary loss less than $100K. innovative entrepreneurial 29 global 29

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32 Qualitative Safety Consequence Criteria 4 Onsite or offsite: Poten.al for mul.ple life- threatening injuries or fatali.es. Environment: Uncontained release with poten.al for major environmental impact Property: Plant damage value in excess of $100 million 3 Onsite or offsite: Poten.al for a single life- threatening injury or fatality. Environment: Uncontained release with poten.al for moderate environmental impact Property: Plant damage value in the range of $ million 2 Onsite or offsite: Poten.al for an injury requiring a physician's care. Environmental: Uncontained release with poten.al for minor environmental impact Property: Plant damage value in the range of $1-10 million 1 Onsite: Poten.al restricted to injuries requiring no more than first aid. Offsite: Odor or noise complaint Environment: Contained release with local impact Property: Plant damage value in the range of $0.1 to 1 million innovative entrepreneurial 32 global 32

33 Qualitative Criteria / Typical Scenario 4 Initiating event or failure Hose leaks/ruptures 3 One level of protection Piping leaks 2 Two levels of protection Full-bore failures of small process lines or fittings 1 Three levels of protection Tank/process vessel failures innovative entrepreneurial 33 global 33

34 Consequence Frequency 4 IV II I I 3 IV III II I 2 IV IV III II 1 IV IV IV III Source: CCPS Guidelines for Hazard Evaluation Procedures, Second Edition I Unacceptable (Should be mitigated with engineering and/or administrative controls to a risk ranking of III or less within a specified period e.g. 6 months) II Undesirable (Should be mitigated with engineering and/or administrative controls to a risk ranking of III or less within a specified period e.g.12 months) III Acceptable with control (Should be verified that procedures or controls are in place IV Acceptable As Is innovative entrepreneurial global 34

35 Risk Mitigation Risk Level A : Risk mitigation required to risk level C or D Risk Level B : Risk mitigation required to risk level C or D Risk Level C : Risk mitigation to risk level D is optional Risk Level D : No further risk mitigation required innovative entrepreneurial global 35 35

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37 Risk acceptance criteria: Criteria used as a basis for decisions about acceptable risk. Example of simple Risk Acceptance Criteria: All avoidable risks should be avoided. Risks should be reduced wherever practicable. The effects of events should be contained within the site boundary. Further development should not pose any incremental risk. Acceptable risk: Risk that is accepted in a given context based on the current values of society and in the enterprise. innovative entrepreneurial global 37

38 Risk acceptance is basically a question of the benefits you hope to receive from accepting a risk. Some people seem to accept a very high risk voluntarily if the benefit they receive is very high to them. An industrial worker may, for example, accept the risk from the plant that employs her because this activity provides her income. Her neighbor, on the other hand, may find that the group (societal) risk from the same plant is totally unacceptable, as she receives no direct benefit from its operations. Who, then is the legitimate decision-maker? innovative entrepreneurial global 38

39 Tolerability refers to the willingness to live with a risk so as to secure some certain benefits and in the confidence that it will be properly controlled. To tolerate a risk means that we do not regard it as negligible or something we might ignore, but rather as something we need to keep under review and reduce still further if and as we can. For a risk to be acceptable on the other hand means that for purposes of life or work, we are prepared to take it pretty well as it is. innovative entrepreneurial global 39

40 Unacceptable level of risk: unacceptable except in extraordinary circumstances (such as wartime), whatever their benefits. Activities causing such risk would be prohibited, or would have to reduce the risk whatever the cost. Tolerable level of risk: tolerated in order to secure certain benefits. In this region, the risk is kept as low as reasonably practicable (ALARP), by adopting reduction measures unless their burden (in terms of cost, effort, or time) is grossly disproportionate to the reduction of risk they offer. Broadly acceptable level of risk: the risk level is generally regarded as insignificant. Further actions to reduce the risk are not normally required. innovative entrepreneurial global 40

41 INTOLERABLE LEVEL (Risk cannot be justified on any ground) THE ALARP REGION (Risk is undertaken if benefited is desired) BROADLY ACCEPTABLE REGION 1 X 10-3 per year (workers) TOLERABLE only if risk reduction is impracticable or if its cost is grossly disproportionate to the improvement gained TOLERABLE if cost of reduction would exceed the improvement gained 1 X 10-6 per year (residential) 1 X 10-5 per year (industrial) innovative entrepreneurial 41 global 41

42 Risk Sacrifice (time, money, trouble) Reasonably practicable is a narrower term than physically possible and implies that a computation must be made in which the quantum of risk is placed in one scale and the sacrifice, whether in money, time or trouble, involved in the measures necessary to avert the risk is placed in the other; and that, if it be shown that there is a gross disproportion between them, the risk being insignificant in relation to the sacrifice, the person upon whom the duty is laid discharges the burden of proving that compliance was not reasonably practicable Edward Vs National Coal Board [1949] (British Court) innovative entrepreneurial global 42

43 LSIR is used as a measure of individual risk This means that the risk is not influenced by population Residential receptors: 1 x 10-6 fatalities per year Industrial Receptors: 1 x 10-5 fatalities per 1 x 10 year -3 Industrial area 1 x 10-6 Voluntary risks:: 1 x 110x 10-3 fatalities per year -5 Residential area Proposed refinery innovative entrepreneurial global 43

44 ALARA is an acronym for "as low as reasonably achievable", which is the risk acceptability framework in the Netherlands. The ALARA principle is conceptually similar to ALARP, but does not include any region of broad acceptability. Until 1993, the region of negligible risk was part of the Dutch policy. Subsequently, it has been abandoned on the grounds that all risks should be reduced as long as it is reasonable (Bottelberghs, 2000). ALARA has, however, gained a somewhat different interpretation in practice. According to Ale (2005), it is common practice in the Netherlands to focus on complying with the upper limit rather than evaluating the reasonable practicality of further action. The unacceptable region in ALARA is, on the other hand, generally stricter than the one in ALARP, and the risk levels usually end up in the same range. innovative entrepreneurial global 44

45 GAMAB is an acronym of the French expression globalement au moins aussi hon, which means "globally at least as good." The principle assumes that an acceptable solution already exists and that any new development should be at least as good as the existing solutions. The expression globalement (in total) is important here, because it provides room for trade-offs. An individual aspect may therefore be worsened if it is overcompensated by an improvement elsewhere. The GAMAB principle has been used in decision-making related to transportation systems in France, where new systems are required to offer a total risk level that is globally as low as that of any existing equivalent system. innovative entrepreneurial global 45

46 MEM is an acronym for minimum endogenous mortality, which is a German principle that uses the probability of dying of natural causes as a reference level for risk acceptability. The principle requires that new or modified technological systems must not cause a significant increase in the IRPA of any per- son (Schabe, 2001). MEM is based on the fact that death rates vary with age and the assumption that a portion of each death rate is caused by technological systems (Nordland, 2001). innovative entrepreneurial global 46

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48 In this life, there is no such thing as zero risk, there is always some risks associated with any activity At level should we tolerate these risks? Two types of Risks Voluntary Risks e.g. driving or riding in an automobile, and working in an industrial facility. Involuntary Risks e.g. exposure to lighting, disease, typhoons and persons in residential or recreational areas near the industrial facilities. innovative entrepreneurial global 48

49 Smoking 1 pack of cigarettes per day Riding a motorcycle Fighting a fire 5,000 2, ,000 1,000 Voluntary Risks Driving a car Pedestrian hit by a car Taking X Ray for diagnosis Involuntary Risks Death by Lightning or tornadoes innovative entrepreneurial global 49

50 Voluntary Risks Risk fatalities (death) per Activity person per yr (x10 6 ) 5000 Smoking (20 cigarettes/day) Motor cycling Car racing Car driving Rock climbing Football Involuntary Risks Risk fatalities (death) per Activity person per yr (x10 6 ) Influenza Leukemia Run over by road vehicle (UK) Run over by road vehicle (USA) Floods (USA) Storms (USA) Lightning (USA) Falling aircraft (USA) Falling aircraft (UK) innovative entrepreneurial global 50

51 Societal risks (Ball and Floyd, 1998) discusses societal risk and different reg- ulatory practices for establishing FN criterion lines. Acceptahle Risk (Fischhoff et ai., 1981) is a pioneering book on risk accept- ability, which evaluates three principal approaches to acceptable risk problems: expert judgment, bootstrapping (accepting what has been accepted in the past), and formal analysis. Reducing Risks, Protecting People: HSE's Decision-Making Process (HSE, 200 Ib) presents the ALARP framework in the decision-making context of the UK HSE. The Tolerability ofriskfrom Nuclear Power Stations (HSE, 1992) explains the principal thinking behind HSE's approach to risk acceptability. Foundations and fallacies of risk acceptance criteria (Johansen, 201Oa) was written in parallel with this book and offers more principal discussions on the use of risk acceptance criteria. Risk and emergency preparedness analysis (NORSOK z-o13, 2010) provides a nice overview of the pros and cons of various risk indicators. Risk evaluation criteria (Skjong et ai., 2007) presents a comprehensive review of risk indicators and evaluation criteria in the marine industry. OffshoreRiskAssessment: Principles,ModelingandApplicationofQRAStud- ies (Vinnem, 2007) discusses trends and risk indicators for harm to people and the environment in offshore industries. innovative entrepreneurial global 51

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