DEVELOPING ERGONOMIC BASED CLASSIFICATION RULES

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1 DEVELOPING ERGONOMIC BASED CLASSIFICATION RULES N J Méry and J McGregor, Bureau Veritas, France SUMMARY Classification societies, as some of the most important maritime safety stakeholders are getting increasingly involved in human casualty prevention at sea and are willing to contribute to setting up ergonomic design standards for ships. This paper presents the initiatives of Bureau Veritas which aim to improve occupational safety onboard through the use of ergonomics at the design and approval stage. The paper will describe the first two steps of the society s strategy to introduce low cost solutions that greatly reduce the risks faced by seafarers. The first step led to the development and publication of a guidance note for the ergonomic design of the means of access onboard (ladders, openings, walkways, etc.). The second ongoing step is the development of a guidance note for the ergonomic design and arrangement of the machinery and control spaces. This second step considers three main topics, namely: occupational health and safety; workplace design and; the human-machine interaction. NOMENCLATURE IMO International Maritime Organisation OHS Occupational Health and Safety STF Slips, Trips and Falls ILO International Labour Organisation GBS Goal-based Standards (new approach at IMO to develop holistic requirements for rules) IACS International Association of Classification Societies ISO International Organisation for Standardisation ASTM American Society for Testing Materials HMI Human Machine Interaction 1. INTRODUCTION There is a need from the maritime industry to increase its standards in terms of Occupational Health and Safety (OHS). Not all of the industry s actors are aware that occupational accidents onboard commercial ships cause everyday injuries to seafarers which can sometimes be fatal. A recent survey of the Norwegian Maritime Directorate s database and Lloyd s Register s Fairplay database found that more than 50% of the deaths recorded by the Norwegian Maritime Directorate were due to occupational accidents and none of these were recorded by Lloyd s Register s Fairplay database. Additionally, these injuries and fatalities induce direct and indirect costs for shipping companies and P&I clubs. Classification societies are among the main actors in maritime safety. Historically, Class has been more focussed on ensuring vessels seaworthiness, they now tend to aim at managing the risks the ship system will encounter. This risk management includes the risk to humans and improving more explicitly seafarers safety by considering the human element as part of the ship system. Class societies are not only implicitly encouraged by the growing human element community to conduct research in the area of human factors but it is also explicitly stated by the International Maritime Organisation (IMO) in the current requirements of Goal Based Standards (GBS) for oil tankers and bulk carriers that classes common structural rules should follow ergonomic design principles 1 [1]. Thus, Bureau Veritas initiated several activities to research and develop requirements ensuring seafarers and surveyors safety onboard merchant vessels. These activities are based on integrating ergonomic design features in the vessel and her equipment through low or no cost rule requirements. In fact, there are two main objectives for making the design safer through ergonomics: Reduce the number of occupational accidents onboard Reduce the number of unsafe acts and so-called human errors onboard It is acknowledged that ergonomic based requirements from guidelines, additional notations or classification rules cannot cover the wide range of ships designs. The ideal solution is to carry out a full ergonomic analysis (Human Factors Engineering) based on these requirements during the design phase of the vessel with a strong emphasis on task analysis. However, this would increase the design costs substantially. Ergonomics driven rule requirements on the other hand provide a framework for ensuring that the vast majority of related risks are managed at almost no extra cost to the design process. 2. FIRST STEP: ERGONOMIC DESIGN OF THE MEANS OF ACCESS 2.1 PREVENTING SLIPS, TRIPS AND FALLS Slips, Trips and Falls (STF) are some of the most common and frequent occupational accidents in the industry. They can happen in many places onboard a merchant vessel: ships motions at sea are very likely to 1 This means that these rules should integrate the seafarers activity in the ship design requirement.

2 cause seafarers to lose balance, wet or oily floors are likely to cause seafarers slipping, dark areas are likely to cause them tripping on obstacles on the floor or bumping into protruding pipes, etc. Surveyors are also exposed to STF accidents while on duty, especially during close-up surveys where they have to closely inspect a great amount of the ship s structures. Moreover, a 2005 study by Jensen et al. [2] shows that STFs account for more than 40% of non-fatal occupational injuries occurring at sea and more than 60% of accidents requiring at least 90 days to recover. We chose to address STFs through the design of the Means of Access (MAs) onboard vessels [3], a strategy which has already been demonstrated to be successful for the offshore industry. Additionally, some research made by the US Department of Navy led to the definition of a general cost model for the introduction of measures for fall protection and prevention (from height) [4]: incorporating fall protection and prevention measures at the final drawing stage will cost ten times more than doing it during the conceptual design; in the same way, the costs will be 100 times higher if the measures are done as a construction modification, 1,000 times higher during start-up and testing and 10,000 times higher during maintenance phase. This accounts for the importance of integrating the human element as early as possible during the life cycle of the ship. Additionally, the design of the means of access is addressed by the IMO amended SOLAS regulations II- 1/3-6 [5] and the revised technical provisions for means of access [6] and the corresponding International Association of Classification Societies (IACS) Unified Interpretations (UI) [7]. These regulations, provisions and requirements present a first basis for the ergonomic design of the means of access however, more detailed requirements for a user-centred design of the MAs, ensuring the safety of seafarers and surveyors, are required. 2.2 THE IMPORTANCE OF USER FEEDBACK When developing requirements based on ergonomic principles for user centred design as we did for the means of access, it is very important and even required that the users participate. Who better than the seafarers and surveyors themselves can assess the design of the means of access? The answer is obvious: nobody. Therefore we collected user feedback through different ways: interviews in office, interviews onboard (we also built ourselves a practical opinion on the reality of using means of access) and questionnaires. 2.3 A RISK BASED METHODOLOGY We used the feedback from surveyors and seafarers for identifying and assessing STF related hazards and risks. The questionnaires were particularly useful for quantifying the risks associated to different places onboard and different means of access. Respondents were asked to assess the dangerousness of the places and means of access on a qualitative scale of severity of injuries (e.g. very dangerous death or disability); they were also asked to assess the frequency of access of the different places. We could finally derive a risk measure from these severities and frequencies. 2.4 ANTHROPOMETRY For the development of ergonomic based requirements it is necessary to analyse: the work environment, the tasks to be carried out there, and the population of users who perform these tasks. We addressed the first two points through the identification of the STF hazards and the safety assessment of the means of access based on user feedback. For the analysis of the population of users, we performed an anthropometric analysis. Anthropometry is the study of the human body dimensions and strength. An anthropometry analysis is required to ensure that the product designed (here the means of access) fits the physical characteristics of the users while he carries out his tasks (see Figure 1 below). Figure 1: Anthropometry in its environment We can illustrate the importance of taking into account the physical characteristics of seafarers by referring to an accident that occurred recently and that could have been avoided if an anthropometric analysis had been done during the design phase of the vessel [8]: in September 2007, three seafarers died onboard an emergency response rescue vessel in the North Sea as a result of both an oxygen deficient atmosphere within the chain locker and a non-anthropometrically sized chain locker access hatch. The first seaman entered the chain locker in order to tie off the chain and collapsed; the second seaman, in an attempt to rescue the former entered the chain locker and collapsed as well; then the third seaman tried to get into the chain locker equipped with a breathing apparatus (BA) but finally had to use an emergency escape breathing device (EEBD) instead

3 since, being a large man, he couldn t descend through the hatch while wearing a BA. Unfortunately, EEBDs are not built for rescue and (also for some other reasons) the third seaman experienced breathing problems and collapsed. Obviously the size of the hatch was not at the origin of the accident but it contributed to the failure of the attempt to rescue the first two seamen and the death of the third one. Thus, we developed dimensional requirements in accordance with the anthropometric characteristics of the population studied for the design of the MAs. For instance, in reference to the accident summarised in this section, openings should be wide enough to allow a large person, wearing a BA to rescue another person situated at the other side of the opening. We used CAD virtual environments representing some typical areas on the ship and virtual manikins as shown on figure 2 hereafter: Figure 2: CAD 3-dimmensional simulations for the anthropometry analysis of the means of access 2.5 THE GUIDELINES FOR THE DESIGN OF THE MEANS OF ACCESS FOR INSPECTION, MAINTENANCE AND OPERATION OF COMMERCIAL SHIPS A guidance note entitled Guidelines for the Design of the Means of Access for Inspection, Maintenance and Operation of Commercial Ships was published in April 2008 by Bureau Veritas [9]. This document provides ship owners, shipyards, marine engineers, naval architects and every stakeholder involved in the design and building of merchant ships with dimensional requirements and practical advice for the design, use and maintenance of the Means of Access. These requirements address in particular the following types of means of access: Walkways, guardrails and handrails Vertical and horizontal openings Vertical ladders Inclined ladders or stair ladders 3. SECOND STEP: ERGONOMIC DESIGN OF THE MACHINERY SPACES 3.1 ACCIDENTS IN THE MACHINERY SPACES During the study on the design of the means of access onboard commercial ships it clearly appeared with the analysis of surveyors feedback through questionnaires that machinery spaces are considered as some of the most risky places onboard commercial ships: the analysis of the feedback showed that even if the severity of injuries occurring in machinery spaces is quite average, the frequency of access (daily and weekly) is high, and this increases the risk a lot. Furthermore, these findings are confirmed by some relatively recent studies. In Hansen et al paper, Maintenance in the engine room and Repair work in the engine room were among the most dangerous tasks in terms of number of notified occupational accidents occurring onboard Danish flag merchant ships for the period. This Danish study was then presented to the IMO at MSC 83 [10]. In addition, the 2005 questionnaire study by Jensen et al. [2] showed that 31% out of the 461 reported injuries (11 countries worldwide) analysed happened in the engine room. According to our work on the means of access, slips, trips and falls related injuries occurring in the machinery spaces representing 37% of the total number of injuries in machinery spaces in Jensen et al. s paper would be partly due to be the bad location or simply the lack of access to some parts of the machinery spaces, making it harder to carry out operation, maintenance, repair and inspection tasks safely. What about the other causes and types of injuries? How can the design of the machinery space prevent occupational accidents? In order to answer these two questions, we logically decided to more comprehensively assess the safety of machinery spaces and research on how to design safe machinery spaces with ergonomic principles. Besides, this particular area appears to be one of the IMO s concerns: in 1998 the MSC Committee of the IMO adopted the MSC circular 834 [11] providing guidelines for the design of the machinery spaces mainly based on human factors related requirements (including ergonomics) aiming to encourage ships designers, shipowners, ship operators, shipping companies, shipmasters and engine-room staff caring about and improving safety and effectiveness of these places. 3.2 HAZARD IDENTIFICATION The methodology we adopted is the same as the one we used for the development of ergonomics-based requirements for the design of the means of access. Thus, the first step is to identify hazards that seafarers face in the machinery spaces. We characterise hazards by a combination of the following three main elements as represented on figure 3:

4 A place or a piece of equipment: machinery spaces are quite different in terms of layout, depending on the type of vessel, her size, her trading area and her type of propulsion. However, all machinery spaces have roughly the same types of equipment and way of functioning: the three primary functions of the machinery spaces are the propulsion, manoeuvring and power supply of the vessel; the five main circuits are the fuel circuit, the lubrication circuit, the air circuit, the water circuit and the electrical circuit. In other words, what we mean by the expression machinery spaces is every room, or piece of equipment which is part of the propulsion system, the steering system or the power supply system. As an example, this definition typically includes the engine control room, the main engine room, the transformer room, the pump room, the steering gear room or the workshops (the latter being part of all three systems through the maintenance and repair activities it implies). A task: seafarers have to carry out many different tasks for operating, maintaining, repairing and inspecting the machinery spaces. These tasks can be carried out on a routine basis, after inspection, or in an emergency situation. A action is defined as a specific task in a specific place. A triggering factor and/or an environmental factor: these factors determine the failure mode of the task carried out. For our analysis, triggering factors will principally derive from a bad/unsuitable/ineffective design of the equipment (design of the controls, the screens, the gauges, and the access to the equipment, etc.) or a wrong/inappropriate action (due to stress during an emergency situation, a failure to follow the procedures, unsuitable procedures, a lack of communication, heavy workload due to a system failure, etc.). Environmental factors are typically temperature, noise, vibrations, etc. Hazards were identified and defined according to the information gathered through interviews of people working or having worked in machinery spaces (exdesign engineer, surveyors, ex-superintendant, ex- first engineers), visits onboard an emergency rescue boat, a ro-ro ferry and a container ship as well as information taken from the International Labour Organisation (ILO) [12] [13] [14] [15] and accident reports from various national maritime investigation bodies (MAIB, MARS, CHIRP, BEAmer, NMD, DMA, etc.). We illustrate our findings by two situations encountered during our visits onboard: The first one describes a hazard present in every engine room. Various maintenance and cleaning tasks require removing some plates from the walking platform in order to access some pipes, valves and other devices. However, this constitutes a risk for someone to fall into the hole on the floor as shown on figure 4 hereafter: Figure 4: A dangerous situation in the main engine room The second illustration raises the issue of relatively small vessels (such as coasters, ferries or HSC) in which the space onboard is restricted. In fact, logically, the economy of space is often done in the machinery spaces since this area has no commercial function. We can therefore have sometimes very little space around some pieces of equipment for maintenance and not enough space to adopt a suitable and comfortable working posture, as shown on figure 5 hereafter where the ceiling in the steering gear room is so low that almost nobody can stand up. Figure 3: Characterisation of hazards in the machinery spaces

5 website or in Andersson & Lützhöft s 2007 paper [16]. 3.3 RISK RANKING In the same way as for the study on the means of access, we used risk in order to rank the hazards identified previously in terms of safety and performance. Risks associated to the identified hazards are based on (1) the severity of injuries and decrease in the performance they are likely to be the cause of and (2) the frequency of the task that has to be performed. Figure 5: Lack of space in a steering gear room The list of hazards should be ideally as comprehensive as possible. We will not present in this paper all the hazards we identified, however some of the hazards very often cited by users and ex users are: Heavy maintenance tasks in the main engine room but particularly in smaller rooms such as pump rooms were pointed out. The triggering factors mentioned are a poor and/or unsuitable arrangement of the lifting and systems. Because of the ship motions one can be crushed by heavy parts being lifted. Sometimes there are no lifting devices and no easy access to the part that has to be moved or maintained; had an emergency situation occurred (a hot fuel oil leakage for instance) it would be very hard to get out quickly because of the lack of space. The temperature in some parts of the engine room is a real concern for seafarers. The temperature can be very high in tropical areas while it can be very low during winter in northern Europe areas for instance. Working during hours in too high or too low temperatures significantly decreases the performance of seafarers and represents an increased risk for being injured. Burns on hot parts of the machinery seem to be very common for seafarers as well since it is quite easy to touch hot pipes inadvertently while concentrating on performing another task. Location of wheels and valves (dangerous or not accessible) can create two types of hazards. They can turn into obstacles or since they are sometimes out of easy reach people have to climb or crawl to use them while balancing in a precarious position which represents an unsuitable working posture for the type of work performed. Some typical examples are highlighted on the US Navy safety centre 3.3 (a) Consequences Consequences are impacts on seafarers health (injury) or impacts on their well being and effectiveness: seafarers and surveyors can be injured while carrying out a task; environmental factors such as noise, vibrations or temperature are likely to impact their well-being and effectiveness as well causing health troubles such as musculo-skeletal disorders. Therefore, we group the consequences that we identified in two categories: Consequences on seafarers health: Minor or severe burns, blows, entanglement, eye injury, sprains, fractures, electric shock, total of partial loss of hearing, total of partial loss of sight, musculo-skeletal disorders, fatigue, etc. Consequences on seafarers performance: decrease in the work effectiveness, decrease in the motivation, decrease in concentration, decrease in cognitive capacities (slow reasoning, poor logic, alertness decrease, and erroneous interpretation of procedures, alarms and signals), decrease in dynamism, decrease capacity of error recovery, risk taking behaviour, etc. Moreover, through the questionnaire, we associate a more subjective severity scale to the actions [specific tasks in specific places] so that hazards are ranked by (1) consequences on health and/or performance (2) direct assessment from users. The scale used is: Very dangerous (fatality, disability) Rather dangerous (severe injuries) Not really dangerous (minor injuries) Not dangerous at all Thus, we can check the consistency and robustness of the assessment of consequences. 3.3 (b) Frequencies The frequencies are mainly taken from the usual operation, maintenance, repair and inspection tasks. The sources of data we used to obtain such frequencies are again expert judgement from user feedback through interviews and questionnaires but we also used several maintenance plans of existing vessels. As a rough general overview of the frequencies, valves are operated several times a week, seafarers have to read many different

6 gauges everyday for inspection, checking or monitoring purposes, safety devices in the main engine room, the boiler room or the main diesel generators room are usually maintained on a weekly basis as is cleaning the means of access and the purifier room and lubrication operations. Many maintenance operations are performed on a monthly or yearly basis while repair activities on the main engines happen more scarcely. 3.3 (c) Risks Risk measures are derived from the information organised in the Table 1 hereafter: Place Hazards Consequences Frequencies Trig. Task Cons. Sev. Freq. factors Table 1: Data for hazards risk-based ranking 3.4 ERGONOMIC / HUMAN FACTORS ANALYSIS We found it not possible, relevant or useful to carry out a full anthropometry analysis for every possible configuration/type of machinery found on the different ships types. Moreover, a huge amount of work has been already done in various industrial areas and in the maritime industry in relation to the micro elements of the ergonomic design of machinery. There is consequently a substantial amount of documents related to designing machinery controls to fit people s physical and cognitive needs and capabilities. Therefore, the novel ergonomic (or human factors) study we are carrying out deals more with the macro aspects of the engine room arrangements for preventing occupational hazards. For the micro aspects we draw on the existing work and incorporate existing standards, advice, guidelines, provisions and best practice from international and national regulatory or standardisation bodies and the industry in order to achieve these goals, namely: IMO requirements from SOLAS, from the circular on the engine room design [11] as well as all documents related to the bridge design, which provide many useful standards and guidance for the design and arrangement of engine control rooms. IACS Unified Interpretations of SOLAS requirements for the bridge design and Unified Requirements as well as IACS internal procedures on the approval of design through ergonomics. Bureau Veritas requirements from classification rules for steel ships and the guidance note for the design of the means of access. ILO guidance documents on occupational health and safety [12] [13] [14] [15]. ISO standards, on the identification colours for piping systems, 8861 on the engine room ventilation, 8862 on the air conditioning and ventilation of machinery control rooms, and on the human-centred design processes for interactive systems, etc. Standards from the industry; for instance, Shell design and engineering practice manuals for human factors engineering. UK P&I s website of useful ideas as seen by the Club s ship inspectors. Standards and guidance from the US Navy health and safety services. We carried out research in two main categories described in the sections below: occupational health and safety and the human machine interaction. 3.4 (a) Occupational Health and Safety (OHS) Health and safety of the seafarers can be ensured by addressing environmental factors such as the air quality and the ventilation, the temperature, the noise and the vibrations or by the design of the workplace. The former addresses middle-long term effects of the environment on health while the latter directly addresses accidents such as slips, trips and falls. 3.4 (b) The Human Machine Interaction (HMI) In the machinery spaces, seafarers are constantly interacting with all the elements and parts constituting the water, air, fuel, and oil systems directly or, since vessels are increasingly automated, very often through switchboards, gauges and many other devices allowing their control, maintenance, repair and inspection. This human machine interaction should be addressed during the design phase in order to mitigate human errors and ensure the performance of people interacting with them. In order to derive the design requirements taking into account this interaction we adopted the three complementary approaches presented by Folcher and Rabardel [17]: The human machine interface approach raises the question: What are the functionalities available to the user through the interface? Criteria for designing a quality interface can be the self-learning capacity, the quality of displays and commands, the adaptability to individual differences, the protection against user errors and transparency. The human machine system approach raises the questions: How does the machine help me to complete the user s objectives? In other words, how does the machine and user cooperate in order to achieve the user s goal? For assessing the HMI, we use some ergonomic criteria such as those defined by Bastien and Scapin for the design of interactive software programs [18]. The activity with instruments approach raises the question: How does the machine change the

7 user s activity? This approach considers the activity of the user and the tasks he has to perform in order to carry out his duty at work. 3.5 FURTHER WORK We are currently deriving requirements for the design and arrangement of the machinery spaces from the human factors analysis in order to develop a guidance note. The guidelines are being developed along with the six main categories addressed in the IMO MSC/Circ.863: Familiarity Occupational Health Ergonomics Survivability Minimising risk through design, layout and arrangement However, the requirements will be grouped in different ways depending on their type and the equipment they address: By type of equipment By situations and tasks performed (emergency, normal operation, repair, maintenance, etc.) By environment (hot, cold, humid, vibrating environment, etc.) By type of vessel By type of human machine interface for systems requiring higher detail cognitive task analysis 4. CONCLUSION A significant amount of work has been done and is being done on the ways to improve occupational health and safety in shipping. Nevertheless, there are not only some areas that still need to be addressed, such as the design and arrangement of the machinery spaces, but also there is a need for development of standards that integrate the numerous different design requirements developed by the various maritime stakeholders. Through our research we are therefore trying to develop these standards based on ergonomics as a common denominator so that approaches for the design of the means of access, the machinery spaces, the deck or the bridge are all based on the same ergonomic principles. However these guidelines will only have an impact if they are used in the design phase of a project. If this is the case, they represent an effective and low cost way to protect seafarers from occupational accidents, illnesses and to ensure a comfortable and effective working environment onboard. Finally, at the time when the maritime sector is struggling to attract sufficient young people into the industry, it appears crucial to show the efforts of the maritime industry to deal with seafarers safety and health aboard merchant vessels. 5. ACKNOWLEDGEMENTS We would like to acknowledge all the persons who were interviewed and who responded to the safety assessment questionnaires, surveyors and BV s ex-seafaring personnel in particular. They participated actively in our research and provided us with some very valuable feedback of their experience at sea or as design engineers. 6. REFERENCES 1. IMO, MSC 85/WP.5/Add.1, Goal-based new ship constructions standards report of the Working Group, December O. Jensen et al., Non-Fatal Occupational Injuries Related to Slips, Trips and Falls in Seafaring, American journal of industrial medicine 47: , N. Méry, M. Lassagne, J. McGregor, Including ergonomics in the design process to address the risks of slips, trips and falls: methodology and application, Proceedings of the 27 th International Conference on Offshore Mechanics and Arctic Engineering, Naval Safety Center website. Acquisition Safety Fall Protection, January IMO, resolution MSC.151(78), Adoption of amendments to the international convention for the safety of life at sea, 1974, as amended, May IMO, resolution MSC.158(78), Adoption of amendments to the technical provisions for means of access for inspections, May IACS, UI SC 191, Unified Interpretations for the application of amended SOLAS regulation II-1/3-6 (resolution MSC.151(78)) and revised Technical provisions for means of access for inspection (resolution MSC.158(78)), Revision 3, March MAIB, Report on the investigation of the work undertaken in a dangerous enclosed/confined space and the consequent attempted rescue onboard ERRV Viking Islay resulting in the loss of three lives at the Amethyst gas field, 25 miles off the East Yorkshire coast UK 23 September 2007, July Bureau Veritas, Guidelines for the Design of the Means of Access for Inspection, Maintenance and Operation of Commercial Ships, NI 537 DT R00 E, April IMO, MSC 83/5/7, Goal-based new ship construction standards Consideration of GBS and

8 occupational health and safety, Submitted by Denmark, July IMO, MSC/Circ.834, Guidelines for the engineroom layout, design and arrangement, January ILO International Occupational Safety and Health Centre (CIS), International Hazard Datasheets on Occupation Ship-Engineer (Machinist), /products/hdo/htm/engnr_ship.htm. 13. ILO, Maritime Labour Convention, ILO, SafeWork Bookshelf ILO, Encyclopaedia of Occupational Health and Safety, 4th Ed., ILO, Geneva, ANDERSSON, M & LUTZHOFT, M, Engine control rooms Human Factors, Proceedings of the RINA Human Factors in Ship Design, Safety and Operation, London, UK, FLOCHER, V & RABARDEL, P; Hommes, artefacts, activités: perspective instrumentale, In FALZON, P (Coord.), L ergonomie, pp , Paris, France: PUF. 18. BASTIEN, C & SCAPIN, D, La conception de logiciels interactifs centrés sur l utilisateur : étapes et méthodes,, In FALZON, P (Coord.), L ergonomie, pp , Paris, France: PUF. 7. AUTHORS BIOGRAPHY Nicolas Méry holds the current position of risk and human factors research engineer at Bureau Veritas (BV) Marine Division s Research Department in the Risk, Sustainability and the Human Element section. He is responsible for developing BV s knowledge and competences on the human element. Jonathan McGregor holds the current position Head of the Risk, Sustainability and the Human Element section at Bureau Veritas (BV) Marine Division s Research Department. He is responsible for the development and management of Bureau Veritas research into human, environmental and asset risk and risk control. His main area of expertise is risk based design.