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Safety Engineering and Risk Management Debate 2012

Henry Tan's picture

This is the discussion blog for the MSc course "Fundamental Safety Engineering and Risk Management Concepts" lectured at the School of Engineering, University of Aberdeen. This course is a core module for the following Postgraduate Taught Programmes:
1. Subsea Engineering; 2. Renewable Energy; 3. Oil and Gas Engineering; 4. Safety and Reliability Engineering

King's College

Since this blog is very congested now, you are encouraged to post on sub-blogs for each topic chosen. 

Discussion Topic 1: Rank top ten severe accidents in energy sector

Discussion Topic 2: Is nuclear power safe for humans and the environment?

Discussion Topic 3: Is fracking for shale gas safe and without damage to community environment? Should it be banned?

Discussion Topic 4: If the Piper Alpha disaster occurred today, discuss the current safety legislative regime that will apply.

Discussion Topic 5: In recent years, millions of solar panels have been placed on roofs around the world. Discuss how safe are they? Discuss the hidden pollution caused by solar panels.

Discussion Topic 6: Discuss safety in wind energy.

Discussion Topic 7: Discuss safety considerations in wave energy system.

Discussion Topic 8: Subsea integrity and reliability management

Discussion Topic 9: Safety and risk management in oil and gas industry

Discussion Topic 10: ONGC Mumbai High Accident (July 27, 2005 @ West Coast of India

Discussion Topic 11: Why is the FAR and SIR measures of fatality considered poor measures from the organisation perpective

Discussion Topic 12: Post Macondo underwater technology

Discussion Topic 13: Safety, Reliability and Integrity Mangement Processes and the Human Factor effect

Discussion Topic 14: Discuss safety in biofuels

Discussion Topic 15: Carbon emissions trading: How viable?

Discussion Topic 16: Global dimming and Global warming, hazardous effect of green house gases on our planet earth

Discussion Topic 17: Should Arctic drilling activities be halted until the Safety and Technology are improved?

Discussion Topic 18: The perceived conflict between safety and production

Discussion Topic 19: The April 16, 1947 Texas city fire disaster

Discussion Topic 20: ALARP concept and health and safety of personel, equipments and the work environment. Friends or foe.

Discussion Topic 21: Safety Integrity Level (SIL) of a system is important. What are the methods in place to assess the SIL of any system?

Discussion Topic 22: The role of safety in view of world energy forecast: striking a future balance

Discussion Topic 23: Implication of the offshore industry toward "zero harmful discharge"

Discussion Topic 24: Safety in Hydropower

Discussion Topic 25: The constant struggle between HSE legislation and human stupidity

Discussion Topic 26: The dangers associated with young and inexperienced workers in the workplace

Discussion Topic 27: Geothermal Energy a clean, safe, environmentally friendly and sustainable energy source

Discussion Topic 28: Your view on iMechanica Safety Engineering and Risk Management Debate

Discussion Topic 29: Tackling occupational hazards in developing countries

Discussion Topic 30: Extending the life of pipeline in the North Sea what are the Safety & Risk challenge

Discussion Topic 31: Prescriptive case, Safety case and the furture of Legislation

Discussion Topic 32: Decommissioning of aged Platforms and Pipelines in the North Sea - Risks and Challenges

Discussion Topic 33: Discuss the future of Biomass as an Alternative Source of Energy- Risks and Challenges

Discussion Topic 34: Can the application of Redundancy Increase Safety and Reliability in the oil and gas industry?

Discussion Topic 35: A different approach to the basic R = P x C formula

Discussion Topic 36: Deep Sea Disposal of Oil and Gas Installations – Acceptable risk

Discussion Topic 37: Reliability in the wake of a mega-stor

Discussion Topic 38: Lessons- how are these capture

Discussion Topic 39: Proposed EU regulation on offshore oil and gas safet

Discussion Topic 40: Does the value placed on human life have an effect on safet

Discussion Topic 41: MyAberdeen versus iMechanica

Discussion Topic 42: Potential and Safety Issues concerning Biogas

Discussion Topic 43: Unsafe acts/conditions during routine tasks in platforms/offshore and how to avoid them

Discussion Topic 44: Inherent safety in process safety management – a practical approach

Discussion Topic 45: Managing the risks and issues associated with a depleting reservoir

Discussion Topic 46: Is it safe to leave the abandoned oil and and gas wells?

Discussion Topic 47: Effectiveness of using RBD, FTA, ETA and Bayesian network in modelling failure of equipments in the industry

Discussion Topic 48 (sub-branch): Safety issues during transportation and distribution of oil and gas.

Discussion Topic 49: Safety issues during drilling operations

Discussion Topic 50: Shale Gas Harmful or not, Economical or not

Discussion Topic 51: Energy landscape of the future and the risks associate

Discussion Topic 52: Human Factors in Process Safety

Discussion Topic 53: Health, safety, environmental and cost issues regarding operation, disposal, and re-use of decommisioned plants

Discussion Topic 54: Quality Assurance/Control -the influence on Safety

Discussion Topic 55: Can the applications of Ergonomics Improve Work Place Health and Safety?

Discussion Topic 56: How safe is using a Personal Floatation Devices (PFDs) in an offshore platform or Helicopter Travel?

Discussion Topic 57: Why did macondo happen and changes it brought to health and safety laws

Discussion Topic 58: Discuss the safety and environmental issues of unconventional crude oil exploration

Discussion Topic 59: Discuss the Strategy of Fire Safety and Prevention in Offshore Installation

Discussion Topic 60: Discuss the Prevention of Slips, Trips and fall in the work place

Discussion Topic 61: Reactive Hazards

Discussion Topic 62: Discuss the Emergency Water Landing in the North Sea

Discussion Topic 63: Discuss the risks and challenges involved in working in a confined space.

Discussion Topic 64: Discuss the risks and challenges involved in simultanous operations or co-activities in Oil and Gas activities.

Discussion Topic 65: Excavation Work in Onshore Pipeline Crowded Areas - Risks and challenges

Discussion Topic 66: Discuss the risks and challenges involved in working at heights

Discussion Topic 67: Discuss the safety aspects associated with using divers in offshore operations

Discussion Topic 68: Discuss Body Mechanics and use of Tools in an Offshore Drilling Platform

Discussion Topic 69: The essence of performing FMEA and FMECA in Safety and Risk Management

Discussion Topic 70: Take a break, relax

other topics

You are welcome to initiate new discussion topics. If you are a student in my class “Fundamental Safety Engineering and Risk Management Concepts” and want to start a new discussion topic, you can do the following:
1. post a new blog entry on iMechanica of your proposed discussion topic;
2. email me ( the blog address;
3. then I will setup the link between the main discussion blog here and your blog.

Here contains information about how to register and post. about
When you have difficulty with posting comments, read node/3132

People from outside of the class are very welcome to join our debate!

PDF icon Continuous Assessment.pdf34.12 KB


Marinos Ioannou's picture

So what I am trying to say is that in this situation,
when a fire takes place and the windows are widely opened in all the 7 floors,
then what will possibly happen is that the oxygen parameter will increased with
affecting the fire to increase to! Additionally, there is another risk issue
about this fact. From my experience, I know that humans when are surrounded by
danger are more possible to act with their instincts than with their logic. So
even if it sounds crazy now, what can happen when a real fire takes place and
the fastest way is from a random opened window, then the instinct choose to
jump from there. There are many same examples happened in the past and many
that happening now. My question is, why having windows automatically opened
while a fire alarm if they can cause more fatalities?

Marinos Ioannou

sotlog's picture

There are a lot of inaccuracies about biofuels and especially ethanol.First myth is that "ethanol uses more energy than it yields".The truth  is that a gallon of ethanol requires 19 times less oil to produce than a gallon ooline(Univ of Bercley,2008).Second myth "ethanol uses too much corn".Ethanol uses 26% of the nation's corn crop on a net basis(USDA,RFA).Moreover,ethanol production requires just 2/3 of each bushel of corn.The remaining 1/3 is fed to livestock in the form of distillers grains(RFA).Another myth is that "ethanol production raises the price of corn and food".Experts from USDA,the World Bank academia and other nongovermental organizations all note that a range of factors influence food prices including oil prices commodity speculation,weather and monetary policies.Moreover,according to USDA American farmers recieve just 12.6 cents of every dollar spent on food.Fourth myth is that "ethanolproduction uses too much water".Only 15% of all corn grown in USA is irrigated.Last myth is that"ethanol emits more greenhouse gases than gasoline.Research from EPA and university of Nebrasca show that current ethanol production provide greenhouse gas reduction between 30 and 49 percent compared to gasoline.Furthermore ethanol use in 2011 reduced greenhouse gas emissions from vehicles by 25.3 million tons-the equivalent emissions from 4 million cars.



Olamide s Ajala's picture

Safety integrity level involves the management of the integrity of any system to certify that it delivers the design purpose, and does not harm life, health or the environment, through the design life.

In subsea control system,based on different probability of failure demand (PFD) the SIL is rated as given below:


1 0.1 to 0.01 PSD (Processs Shut Device)

2 0.01 to 0.001 ESD (Emergency Shutdown)

3 0.001 to 0.0001 HIPPS

4 0.0001 to 0.00001 RARE

Due to these probability of failure of demand given above , different emergency shut down and protection of valve (Directional control valves)are put inplace to protect the integrity of the subsea device.

Similarly, in society measures of risk with probability of failure between 0.0001 and 0.00001 , safety measures are put in place to mitigate this hazard to ALARP . This involves proper risk asssement procedure of every operation and various integrity management programs which includes but not limited to comprehensive subsea inspection programs (such as flooded member inspection through the use of ROV and TOFD weld inspection) ,jacket online structural monitoring(used by CNR),FMEA,HAZOP,HAZAN and JSA.


subsea integrity lecture note

Subsea control lecure note

Olamide s Ajala's picture

A cargo ship explodes at dockside in Texas City, Texas due to explosion of ammonium nitrate. The blast and the fires that follow kill about 600 people and injured 3,500 more.

The loss of property excluding marine (which was not ascertainable) is estimated to be $35,000,000 to $40,000,000.

Like every other major disaster in the late 60’s, the disaster can be attributed to human integrity loss either directly or indirectly due to ignorant in handling of hazardous chemical.

Proper storage away from highly combustible commodities as well as labeling of hazardous chemical containers is of paramount vitality. The label should be red in color with the words "Hazardous Chemicals" - :Ammonium Nitrate" - "Handle With Care" to make people aware of the threat it poses.

With the number of fatalities involved in this disasters,it would have been expected that safety regulation cases should have emerged to prevent other major incident that occurred in 1966 (Aberfan disasters) and flixboough (1976) disaster after this texas disaster.

Therefore, my question is why do the Health and safety regulating authorities had to wait till 1984 to establish CIMAH? which would have been more effective in preventing other disasters which occurred much after this texas disaster.


Olamide Sherifah Ajala
Student ID:51230562
Course:Sub sea Engineering

sotlog's picture

As for the idea of imechanica, i would characterize it trailblazing and always being into the right direction but I have some objections.First of all in the begining there were few subjects for discussion, while now there are too many for someone to comment.Secondly there are quite a few posts for nearly 100 students so it is considered to be impossible to read and understand the meaning of all the articles .So in that occassion we just upload a post and continue doing so. That is the reason we can are not able to learn. Furthermore ,there would be a limit whether how many posts can a student upload for one topic. I mainly propose that nobody can upload over 3 posts for a topic.The most crucial issue is that we must not change the rules of the "GAME" in the middle of the assignment. The minus is not in the right direction. A teacher must not punish their students but  must educate them. In addition, the teacher should firstly talk to the class or to the class rep about plagiarism and then discuss with the students about what measures should be taken.


Hanifah N. Lubega's picture

A lot has been said in regard to this topic, from the opinions on the role of regulation to proactive measures and risk management. All these are safety measures including the predictive mechanisms like the probability and reliability theorems, but accidents still occur and several fatalities are being recorded. This brings me to the question that everyone has been asking, “How safe is safe enough?” In my opinion I would say I am safe if am not exposed to any possible risk, but the again there are unpredictable and unforeseeable hazards like natural hazards and the unpredictable future events. Engineering has played a significant role in improving the reliability of systems with these probability failure methods but the accidents still occur anyway, which takes me to the question of “Who is responsible?”

Take a case of this blog issue for example and assume it was a technology/equipment designed to handle some safety concerns in a system. The Engineer, Dr. Tan, has researched and designed it to serve the purpose of ensuring system reliability (continuous assessment) and has to present it to a panel of stakeholders to make a decision on its implementation. Some of the stakeholders may look at the consequences of not having this particular technology, available alternatives, while others may be restricted by costs involved. There maybe several alternatives but they may have different failure rates and reliabilities and/or people that may challenge the technology and hence not implemented.  In the end when a hazard occurs, fingers are pointed. Where am I goin with this? I think all the project stages right from design to implementation, decisions have to be made. Sometimes the law or available regulations may help in such a scenario but there are some that are not prescriptive in nature, that is, the may not give particular codes of structures or reliability although the goal maybe ensuring safety. It leaves the decision to the Engineers or organisation in charge. In my opinion it all comes down to human factors.

In my country, Uganda forexample (probably similar to other countries), the government has a lot of interest the oil and gas activities and sector at large. And their main aim is to earn revenue from the resource while minimising cost and it is the same government that is responsible for these regulations. Safety is often ignored or if considered, the degree of safety is not a concern per say. The LRET special lecture I attended on Thursday gave me a lot of insight on safety, reliability and risk management. The Professor discussed several issues and critically analysed the technical causes of the Alexander Kielland accident which according to his research was due to several failures like poor design of the structure, welding problems and fatigue in structure among others. What all this brought to mind was that there was someone responsible for these designs and maintenance inspections forexample but why the failures? The human factor comes in again, Or maybe the costs were too high so decisions of available alternatives had to be taken (taking me to organisational factors). All in all, someone/individuals with sound mind have to make decisions.

The probabilities of failure/reliability of systems maybe accurate enough to address safety concerns but most importantly the mind set of decision makers on the importance of safetyand risk management and the willingness to attach a cost to safety especially in the oil and gas sector where environmental and health risks are high MUST be handled.   


My opinion

sotlog's picture

What is biolulobricant?Biolubricants applies to all lubricants which are both rapidly biograde and non toxic for humans and the environment.A biolubricant can be  vegetable based oil and it can be based on synthetic asters manufactured from modified renewal oils or from mineral oil based products.Biolubricants have some advantages against oil based lubricants.First of all biolubricants have higher flash point and superior viscosity than lubricants.Flash point reduces smoke so provides a less smoky working environment.Furtheremore, biolubricants have ao chemical additives such as chlorine and sulphur.This fact does the biolubricants to have better lubricity than lubricants.The added lubricity also reduces the friction.Les friction reduces wear on cutting tools so extended tool's life.However biolubricants are not environmentally friendly but environmentally acceptable!!


Jumat Salimon Nadia Salih and Emad Yousif (2010)Biolubricants:Raw materials, Chemical modifications and Environmental benefits


sotlog's picture

What is biolulobricant?Biolubricants applies to all lubricants which are both rapidly biograde and non toxic for humans and the environment.A biolubricant can be  vegetable based oil and it can be based on synthetic asters manufactured from modified renewal oils or from mineral oil based products.Biolubricants have some advantages against oil based lubricants.First of all biolubricants have higher flash point and superior viscosity than lubricants.Flash point reduces smoke so provides a less smoky working environment.Furtheremore, biolubricants have ao chemical additives such as chlorine and sulphur.This fact does the biolubricants to have better lubricity than lubricants.The added lubricity also reduces the friction.Les friction reduces wear on cutting tools so extended tool's life.However biolubricants are not environmentally friendly but environmentally acceptable!!


Jumat Salimon Nadia Salih and Emad Yousif (2010)Biolubricants:Raw materials, Chemical modifications and Environmental benefits


sotlog's picture

Geothermal energy is the natural thermal energy from the magma of the Earth's core that leaks from the hot interior of the planet to the surface or through volcanic flow or through fractures in the subsurface that spurt steam and hot water.The heat transfer takes place in two ways:heat conduction from the inside tothe surface at the rate of 0.06W/mm andwith transport streams(entry into the earth's crust of molten magma from the deeper layers of it), but limited to areas near the boundaries of tectonic places due to volcanic and hydrothermal phenomena.The advantages of geothermal energy are the cost saving because geothermal energy involves low running costs since it saves 80% costs over fossil fuels.Secondly geothermal energy does not create pollution and help in creating clean environment.The gases that releases the geothermal system are not very harmful for the environment.Last but not least the direct use makes geothermal energy cheaper and affordable.Although the initial investment is quite expensive in the long run with big cost saving is provided quite useful.




sotlog's picture

Biomass is any relatively new organic material which comes from the process of photosynthesis.The energy of biomass is from vegetable and animal materials.Biomass crops produce oxygen and reduce carbon dioxide.It is very low in sulphur reducing the production of acid rain.Furtheremore biomass is more effective means of acquaring energy compared to oil supplies.One of the most crucial advantages of biomass is that is available in almost all parts of the world except desert areas.So if there is a good feedstock can be produced cheapily.The future of biomass is in the field known as green chemistry.Current research is very promising for various products such as bioplastics,green chemical products(detergent),plant fibers used to manufacture insulating materials and plant fibers to repace convetiona plastic in the production of dashboards and other automobile components.The only thing that future technologies must do is to minimize biomass' carbon footprint to ensure a more environmentally acceptable energy source.



Olamide s Ajala's picture

There are different types of nuclear power reactor from boiler water reactor(BWR),Pressurised heavy water reactors(PHWR),LWR ETC. With different advances in nuclear power tecgnology, the old generation nuclear power reactor are been phased out to achieved a more reliable and safe system of power generation since nuclear power is with little or no green house gas emission compared to others.

The older generation nuclear reactor or technology(GEN I) didn’t incoprate enough safety in the design process that is one of the reason why we had the fukashima disaster. With the new technology in nuclear energy such as GEN III and GenIII+ among others the relevance and advantages can be summarised below:

It is an essential part of energy mix.

It supports 3 pillars of sustainable development(social economic and environmental)

It can reduce dependency upon energy imports

It has a low CO2 emitting energy source

It offers a secure suplly of base load energy

Hence, Nuclear energy is the new future of safe and clean energy generation


Amec Process and energy Industry lecture.

Olamide Sherifah Ajala
Student ID:51230562
Course:Sub sea Engineering

Alabi Ochu Abdulraheem's picture

Over reliance on non-renewable energies as major source of energy is causing drawbacks to some nation’s development. The sun, which is the main source of energy for solar panels (renewable energies) has other benefits such as keeping the earth warm, providing food for green plant etc, would make the earth a lifeless planet in its absence.
This form of power generation is more environmental-friendly and a safe source of fuel compared to fossil fuels. One of the risk with this is the photovoltaic cell which do contains hazardous materials, that wouldn’t be released to the atmosphere unless there is a damage to the panel.
The cost of operating the solar panel is very expensive and the technology is not that efficient due to the percentage of the day we get exposed to the sun. the risk associated with a damaged solar panel  is very high due to the high consequences of a damaged respiratory system by inhaling silicon dust. A very high risk is also associated with natural habitat, that is land use space.
Reg no: 51231595

Igwe Veronica Ifenyinwa's picture

Geothermal energy uses the heat energy of the
Earth to produce heat or electrical power for humanity’s use. Geothermal works
as an alternative energy source because the inside of the Earth is much hotter
than the surface. My position is that geothermal energy is a renewable energy
source which is clean as it does not pollute, and is also very well suited for
home heating and cooling.
Geothermal energy, the heat is extracted directly unlike crude oil that you
need to burn it. Burning reduces the amount of heat capable of being obtained
if effected directly . Hence, the efficiency of the process is reduced.  Also the volume of
water is almost constant as it is recycled back to the ground, heated up and
reused, but the crude oil is not recyclable in this regard

Geothermal heat pumps for
ground source heating do have higher capital costs but is offset by their lower
operational costs compared to other forms of domestic heating and cooling
(HVAC) systems. Generally speaking, the lifespan of a geothermal heat pump installation is much longer than for a
conventional heating and cooling system, but their overall economic benefit and
payback period will depend primarily on usage and the relative costs of utility
supplied electricity and fuels used for heating and cooling the home, thus
supporting the view that Geothermal energy is a clean, safe, environmentally
comforting and massively sustainable energy resource.

Kyeyune Joseph's picture

Nuclear power is generated from fission/fusion of radioactive elements such as Uranium. At the moment, about 30 countries are producing electricity from nuclear power plants. As regards to safety of nuclear energy, a number of issues do arise both positive and negative. They include the following:

On the positive note, considering carbon footprint or carbon dioxide emissions, this form of energy can be considered clean when compared to other power sources such as coal, oil and gas. Additionally, if considering quantities of waste from a typical nuclear plant per a year, this form of energy produces less waste as compared to other sources of energy such as coal. According to the International Energy Atomic Agency, a typical Light Water Reactor will produce 6million tonnes of waste annually in comparison to 20million tonnes of carbon dioxide released by a coal powered plant of similar size into the atmosphere moreover in addition to other effluents. 

However, on the other side of the coin, most of the nuclear plants are operated on open cycles. This means that they cannot recycle spent fuel. Only five countries (UK, USA, China, Russia& France) have plants that operate on closed cycles. This means that plants with open cycles are facing challenges of nuclear waste that is accumulating. This poses the biggest threat to human life due to its radioactivity. At the moment, there isn’t any safe waste storage technology available. Finland is pioneering geological storage. However, its effectiveness is still questioned.
Ability to withstand disasters such as earth quakes and Tsunamis like in Japan is also another concern as regards nuclear energy. Though it can be argued that the Japan case wasn’t actually a failure of nuclear reactor system but rather power generators supplying coolant pumps, it should be noted that reactor’s failure to cope with the situation led to disasters that created serious safety concerns. 
Weapons proliferation is another safety issue in nuclear energy especially from nuclear waste. Plutonium from nuclear waste can be used to make weapons that in reality threaten existence of human kind!
In lieu of the above, I would argue that unless a safe nuclear waste depository method is devised, this form of energy is not safe for humans and the environment.

Marinos Ioannou's picture

Just one day after the official agreement of
BP to pay the record amount
$4.5 billion
penalty to the charges for Deepwater
Horizon oil spill, a new accident occurred just 20 miles South-East of Grand
Isle in New Orleans. The first reports claim that 22 people were on the
platform during the fire; from them the 11 are injured while, at least 4 are in
critical condition and 2 of them are missing. Meanwhile, oil sheen was created
around the platform and just after the accident occurred a local oil spill
hazard dealing company approached the rig to perform their safety measures.
Firstly, the main target was to allocate and help the two missing people and
then deal with the rest. The platform was not producing oil unlike Deep-
Horizon oil rig but still had approximately 20 gallons oil in the line. The
first investigations showed that the fire was caused by a crew member while
forming a maintenance work trying to cut a 3-inch oil line with a torch.
Unlikely, the line was containing hydrocarbons that finally caused the fire. 

Marinos Ioannou

Abiaziem Davidson's picture

Safety and Risk Management is challenge oil and gas industry must contend with an array of health and environmental concerns throughout its range of operations. In the face of increasing regulatory oversight, as well as increased public scrutiny, oil and gas industry need to implement effective safety management systems to help protect its workers, the general public and the environment. The approach that works well at an offshore installation may not be the best option for a refinery. An effective risk management system needs to offer solutions tailored not only to the industry, but also to the specific company and the sectors in which it operates.

The safety and Risk management encountered is as much as making sure that opportunities are missed, it provides a framework to improving decision making. It involves identifying risks, predicting how probable they are and how serious they might become, deciding what to do about them and implementing these decisions. Safety and Risk analysis and subsequent risk mitigation provides financial information to potential lenders, promotes equity providers for project scenario. It improves project or business planning by answering what if questions with imaginative scenarios. Safety and risk management in oil and gas industry provides alternative plans and appropriate contingencies and consideration concerning management as part of risk response. Decisions are supported by thorough analysis of the data and estimate can be made with greater confidence both technical and financial. 

Safety and Risk management in oil and gas industry is one of the most important issues facing oil and gas organisation today. Safety and Risk management can be considered as the sustainability of a business in the environment it is in. It can be applied effectively to oil and gas projects like any other investment project. The results of risk and safety analysis, both sensitivity and probability can identify the quantitative effect on a project economics should such risk occur. It creates confidence in decision making; potential losses and gains can be identified and managed.

Common factors that cause major accidents in Oil and Gas Industry are: lack of safety culture among the workers, lack of real commitment to safety by supervisors, inadequate hazard analysis (example Job Safety Analysis) and design for safety, Inadequate learning from prior events, confusion between occupational and system safety and belief that process accidents are low probability.


Leveson .N.G (2011), ‘Risk management in the oil and gas industry [online] available at [accessed on 8 December]  


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