Engineering in an Age of Limits

Discusses the role of engineers as society enters an Age of Limits — particularly with oil supplies.

Monthly Archives: October 2014

Regress

Flying Car

Flying Car – 1947

Because we are running into resource and environmental limits we are learning that exponential growth on a finite plant cannot continue. One of the many aspects of our professional lives that will be affected by this change is industrial safety. We will be challenged to make sure that we retain the concept of Safety as a Value and we will need to learn how to design and operate facilities to be safe at a time when resources are increasingly constrained.

The title of this week’s post is taken from a phrase I have often used when leading hazard analysis studies such as HAZOPs. Often one of the leader’s biggest challenges is to get the team members to accept that serious events can happen, i.e., to get them to “think the unthinkable”. Ironically I have found that achieving this acceptance can be a particular problem in those facilities which have a good safety record, where standards are high and the team members consistently exhibit a high level of professionalism. In such situations the leader can have a hard time persuading the team members that risk is never zero, and serious accidents can happen anywhere and in any place. These team members can have trouble ‘thinking the unthinkable’. They will make statements such as, “I’ve been here fourteen years, and never seen that” — with the unspoken follow-on, “. . . therefore it cannot happen”. On the other hand, at a facility that has just experienced a serious accident everyone accepts that ‘it’ can happen. Indeed, one of the most effective actions that a corporation can take following a bad event is to have as many employees as possible come from other sites to look at the destruction in order to make them realize that bad events really can occur.

The point of the above discussion is to show that we all tend to get trapped into linear thinking — we believe that tomorrow will be pretty much a continuation of today without any major changes. And generally it is. But sometimes conditions change radically and over a short period of time — as seems to be occurring now as we enter the Age of Limits. And sometimes those changes are not what we want. Most of us have spent our careers living and working in a time of material and technological progress. With respect to industrial safety, for example, modern electronics and computer systems have allowed us to install sophisticated safety instrumented systems. Similarly advances in techniques such as vapor dispersion modeling improve our ability to analyze risk. Hence, given that most of us think linearly, we take it for granted that technological progress will continue and that safety will steadily improve. But it is possible for progress to stop; even more disturbing, it is possible for progress to go into reverse and become regress.

Airplanes, Cars and Moonshots

That fact that technology does not always progress was brought home to me earlier this year as I was sorting through some family pictures.

Kampala 1971

Kampala 1971

The picture above is of a VC10 airplane. I took the picture in the year 1971 at the start of my journey home from Uganda after serving in Africa as a volunteer teacher. It shows how little airplane design has changed in the last 50 years. The VC10 had an aluminum body, swept-back wings and was powered with four turbo-jet engines. The only major external change since then is that we would not put two engines adjacent to one another now — if one of those engines were to catch fire the one next to it would probably ignite also.

The lack of change in airplane technology becomes clear if we compare the specifications for a VC10 with a modern airliner of roughly equivalent capacity: the Boeing 737-700.

                                               VC10            737-700
Passengers                              109                     126
Cruising speed (km/hr)       900                    962
Range (km)                          9,000                  6,370

Of course the details for each airplane depend on many factors, particularly the model number, but the broad conclusion is clear: the basic design and performance of airplanes has not changed all that much (I could not find data for the fuel consumption per passenger for each model — I suspect that the 737 is much better in that regard; it also has a smaller crew — thus saving money, probably as a result of on-board electronics).

But even here some of the changes represent regress, not progress. In 1971, even though I was an impecunious student, a free hot dinner was served on plates with metal silverware. Pillows were provided as a matter of course and there was actually sufficient leg room. Most remarkably there was no security — none; I just showed my boarding pass and walked on the airplane. And, in flight, when I got bored I asked to visit the cockpit and was welcomed up front — no questions asked. If I tried that now I would be arrested.

Carevelle

Carevelle

Stepping back in time a little bit more, the very first flight that I ever took was in the year 1967 and the airplane was a Finnair Caravelle. As the picture shows, that airplane, which made its first flight in the year 1955, looks quite up to date. Not much has changed.

Concorde

Concorde

We conclude, therefore, that airplane design and performance have not changed radically in fifty years or more — such improvements as have occurred have been incremental and mostly to do with cost savings. Indeed, if there have been radical changes they have been in the other direction. Five years after my 1971 flight in a VC10 the Concorde Supersonic airliner made its commercial debut. It was the fastest commercial airplane in the world with a cruising speed of 2170 km/hr (1350 miles per hour), more than twice the speed of sound. A London to New York crossing took a little less than three and a half hours. By contrast, the modern Airbus A380 has a top speed of 1020 km/hr and takes about eight hours to cross the Atlantic.

Not only was the Concorde radically innovative in its design, it was “an absolute delight to fly, it handled beautifully. And remember we are talking about an aeroplane that was being designed in the late 1950s – mid 1960s. I think it’s absolutely amazing and here we are, now in the 21st century, and it remains unique.” John Hutchinson. The Concorde, which was a gas guzzler, was withdrawn from service in 2003 because the airlines could make more money selling first class seats on subsonic airliners.

Kampala 1971

Kampala 1971

The lack of technical progress can also be seen in the automobile. The day before I went to Kampala airport to catch my VC10 flight I took the picture shown on the left of cars in downtown Kampala. Once more, the basic technology has not changed. Modern cars are safer, more reliable and have electronic gizmos such as satellite navigation systems. But they use the same basic technologies as those 50 year old cars: an internal combustion engine running on gasoline, four wheels, two rows of seats and a driver behind a steering wheel.

Apollo-1A final example to do with technological regress is the collapse of manned space flight programs. The Apollo program put a man on the moon in the year 1969. Five subsequent missions landed astronauts on the Moon, the last in December 1972. In these six flights twelve men walked on the Moon. Now, if the United States wishes to put a man in space — let alone on the moon — NASA is obliged to hitch a ride on a Russian rocket.

Causes of Regress

Peter Thiel

Peter Thiel

Peter Thiel, PayPal founder, once said “We wanted flying cars, instead we got 140 characters“. In spite of the fact that he himself has made a fortune in information technology, he states, “. . . though computer technology has witnessed a ‘relentless’ growth in recent years, other sectors have not seen significant progress in innovation . . . We are no longer living in a technologically accelerating world . . .There is an incredible sense of deceleration.”

Thiel attributes the problem to the fact the many industries, including the energy industry, are over-regulated, whereas the information and software businesses have been relatively free of regulation. But his response, although it is likely to be true, is not sufficient. Why have we not significantly improved the basic technology of automobiles and airplanes? Indeed, why — using the Concorde and the Apollo missions as examples — do we seem to be regressing in some areas? I suggest that the answer to these questions is energy, or more precisely, the cost of energy extraction. We make good progress in areas such as electronics because the energy requirements to build a laptop computer, say, are nowhere close to the requirements for developing a new space program that would allow ordinary people to visit the moon.

Moreover, as noted in Nine Pounds of Gold, we are spending more of our energy just to find and produce the energy we need to replace the depleted reserves. When ERoEI was 100:1 we could invest one barrel of oil and get 100 barrels back. With the net 99 barrels we could invent jet engines, send men to the moon and build freeways. Now, with ERoEI for new projects coming in at less than 20:1 (and not even 1:1 in some cases), we only have 19 or less barrels of energy to use as we wish — and most of that is spent maintaining the systems that we already have in place. There is virtually nothing left over, so we have no choice but to cut back on technological developments.

And there is a more subtle issue to consider. A natural response to the problems with oil supply and private transportation is to transform automobiles such that they run on electric motors, not internal combustion engines. But the energy cost of making such a transformation would be enormous and would have to be spread out over many, many years (after all, there are something like 0.75 billion fuel-powered vehicles – automobiles, trucks, ships and airplanes – in the world).

Moreover, when all of the embedded energy costs associated with electric vehicles, such as batteries that need replacing fairly frequently and the energy used in order to generate electricity from fossil fuels, are considered it may be that the a transportation system based on electricity rather than gasoline and diesel does not use less net energy after all. (What is needed in situations such as this is systems thinking — in a future post I will suggest that this is a great strength of process safety professionals and is a skill that will be very valuable in coming years.)

Safety

Pedestrian-Crossing-1The focus of these posts is on industrial safety, and there is no reason to believe that the safety business is exempt from the drag that the cost of energy will put on all aspects of business. It is true and commendable that safety has improved so much in the last two decades. But much of that improvement can be attributed to two items — the use of advanced electronics and the implementation of behavior based safety programs — that are not energy intensive. Our challenge will be to develop safety programs and ideas that require a minimal use of energy.

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Nine Pounds of Gold

Nine Pounds of GoldLast week’s post showed that the idea of Safety as a Value is not baked into our genes — it is in fact a cultural artifact that developed during the early phases of the Industrial Revolution, i.e., the first half of the 19th century). The post then went on to note that we are entering an Age of Limits and that one consequences of the change will be that industrial professionals will face a serious challenge: how to maintain the moral and ethical idea of safety as a value at a time when economic screws are tightening.

But, before pursuing this idea further it is useful to consider just what is meant by “The Age of Limits”. This is a complex and difficult topic; but can be boiled down to three issues:

  1. Natural resources, particularly oil, are becoming ever more expensive to extract.
  2. We are running out of places to dump waste products such as CO2 or plastics.
  3. In order to maintain economic growth government, businesses and individuals have all taken on immense amounts of debt.

We will look at the first of these — Resource Limitations — in this post.

Sea-3

The following quotation is taken from the article Is there gold in the ocean? posted at the National Oceanic and Atmospheric Administration’s web site.

Ocean waters do hold gold – nearly 20 million tons of it. However, if you were hoping make your fortune mining the sea, consider this: Gold in the ocean is so dilute that its concentration is on the order of parts per trillion. Each liter of seawater contains, on average, about 13 billionths of a gram of gold.

There is also (undissolved) gold in/on the seafloor. The ocean, however, is deep, meaning that gold deposits are a mile or two under water. And once you reach the ocean floor, you’ll find that gold deposits are also encased in rock that must be mined through. Not easy.

Currently, there really isn’t a cost-effective way to mine or extract gold from the ocean to make a profit. But, if we could extract all of that gold, there’s enough of it that each person on Earth could have nine pounds of the precious metal.

The point of this example is to show that it is not the absolute amount of a resource that matters — it is our ability to extract it economically. In the case of gold it will never make economic sense to extract it from the sea. So much for our nine pounds of gold.

With regard to gold it really doesn’t matter how much the extraction process costs — the metal is not a fundamental necessity of our civilization. But the same cannot be said of oil and other hydrocarbon fuels such as natural gas and coal. As it becomes increasingly expensive to extract them from the ground there will be less energy (hence money) left over to fund other activities — including safety. And if ever we reach the point where the net production of energy of oil or gas approaches zero then we are in very serious trouble indeed. One of the many consequences of such a situation could be that we revert to a moral climate similar to that of the early nineteenth century where safety is no longer regarded as a value, or at least it is seen as the responsibility of the individual worker not of the company that employs him or her.

To reiterate, whenever the topic of resource limitations comes up the initial reaction of most people is to consider the overall amount of that resource. “There is plenty of oil in the ground, so we will not run out of it for many, many years.” But, as the example to do with the nine pound gold bars showed, the key question is not “How much is available?” but “How much can be extracted economically?” The issue is not how much of them are in the ground but about the rate and economics of the extraction process.

And in order to address those questions we need to understand the concepts of Net Energy and Energy Returned on Energy Invested (ERoEI). This can be done by thinking of the money not in terms of dollars (or euros or pounds) but in terms of barrels of oil (or cubic meters of gas or tons of coal).

Gross energy is the energy available after oil has been extracted from an oil well or after coal has been mined. But it takes energy to find, produce and consume energy. And it takes yet more energy to convert energy from one form to another (say coal to electricity). Therefore what really matters is not gross but net energy, which can be defined as follows.

Net Energy  =  Gross Energy  –  Energy Expended

Therefore, if a company invests 10,000 barrels of oil in a new oil well and produces a million barrels over the life of the well we have the following values:

Energy Expended  =       10,000 barrels
Gross Energy          =  1,000,000 barrels
Net Energy              =    990,000 barrels

Energy expended includes the energy needed to drill the well and then transport the oil to the customer. It also includes the energy needed to fabricate the steel for the drill rig, the energy used by a refinery to convert the oil into usable products, even the gasoline used by the workers when they drive to work should be included.

ERoEI is another way of looking at Net Energy. It is defined as:

ERoEI  = Energy Output / Energy Input

Using the sample figures provided above the value for the notional oil well is,

EroEI  =  990,000 / 10,000  =  99

Spindletop

Spindletop

This is obviously a very good return on investment; it is what was obtained in the early days of the oil industry in Texas in the 1930s and in Saudi Arabia in the 1950s. The picture of the Spindletop blowout in the year 1901 illustrates the exuberance of a high ERoEI.

By definition any energy investment that has an ERoEI of less than unity does not make sense. In practice many analysts suggest that if the value is less than five then the investment is questionable, largely because most ERoEI calculations exclude many items which really should be included.

One of the challenges in calculating ERoEI is determining the boundaries of any particular energy investment or project. For example, with regard to drilling an oil well the following energy items would most likely be included:

  • Power for the drill rig;
  • Fuel needed to move the drill rig to the site;
  • Fuel needed to transport the produced oil to the marketing hub; and
  • Electricity needed to keep the site office running.

However there are many other energy costs associated with this activity that are likely to be overlooked. These include:

  • The energy used to make the steel used for the drill rig and for its fabrication;
  • The energy used to construct the factory that makes the steel for the drilling equipment;
  • The fuel needed to plug and abandon the well at the end of its life; and
  • Even the energy used by the advertising company to create TV advertisement for the gasoline produced.

The issue becomes even more complex when issues such as shared resources for two projects and the multiple sources of electricity are considered. It is for these reasons that an economic level for ERoEI of five rather than one is often used — there are many energy inputs to a project that are likely to be overlooked.

As already noted, in the early days of the oil industry ERoEI values of 100 or more were commonplace. However it is always the low-hanging fruit that is picked the first so overall ERoEI has dropped as oil, gas and coal have become more difficult to extract. For example, it requires a much greater energy investment to produce oil from a deepwater well than it does from a shallow well located onshore close to market.

Due to the boundary condition problems just discussed and also because conditions change with time it is difficult to develop accurate ERoEI values. Moreover, there are often hidden factors such as government subsidies that skew any analysis. Given these caveats some very, very rough numbers are provided below.

Hydro                                       100
Oil (conventional onshore)    20
Wind                                           18
Oil imports                                12
Natural gas                                10
Solar                                             5
Shale oil                                       5
Bitumen tar sands                     3
Ethanol from corn                    <1 to 5

Regardless of the energy source ERoEI for society overall is declining inexorably and new technologies and sources of energy have lower values than more traditional sources (with some exceptions — the cost of solar panels has come down a lot in recent years, although even in this case there is a large amount of embedded energy in a solar panel, and that energy likely came from oil, gas or coal.)

There are also qualitative issues to consider. For example, low ERoEI projects generally impact the environment much more adversely than those with a higher value. In the “good old days” all you had to do was “stick a straw in the ground” and high quality oil flowed under its own pressure into the production pipeline. No longer — now the development of resources such as the bitumen tar sands has a huge environmental impact. And the Deepwater Horizon/Macondo catastrophe showed just how severe the environmental problems to do with deepwater drilling can be.

Political issues can also be a factor. For example, ethanol produced from corn may have an ERoEI that hovers around one, hence it does not make economic sense to bother with this activity. But the ethanol does provide a local source of fuel thus providing those countries that grow corn and make ethanol with some political independence. And the production process provides jobs for the local population.

Climate change is another qualitative issue. Gas may have a lower ERoEI than coal but it puts less carbon dioxide into the atmosphere and so contributes less toward global warming.

But the bottom line is that we are using more and more of our energy resources to create usable energy — which means that there is less energy (money) left over for all the other activities that we would like to do — including improving safety.

Greer-John-1

John Michael Greer

In a paper published in 2005 – How Civilizations Fall: A Theory of Catabolic Collapse – the blogger John Michael Greer states,

. . . the process that drives the collapse of civilizations has a surprisingly simple basis: the mismatch between the maintenance costs of capital and the resources that are available to meet those costs. Capital here is meant in the broadest sense of the word, and includes everything in which a civilizations invests its wealth: buildings, roads, imperial expansion, urban infrastructure, information resources, trained personnel, or what have you. Capital of every kind has to be maintained, and as a civilization adds to its stock of capital, the costs of maintenance rise steadily, until the burden they place on the civilization’s available resources can’t be supported any longer.

Now this is very big picture thinking indeed. We are confining our discussions here to the value of safety. In the context of the discussion at this post, what Greer is saying is that we will spend more and more of our available net energy (money) on simply finding and producing new so new sources of energy to replace what we are using up. This means that there will be less net energy (money) available for everything else that we want to do — including improving safety, whether it is the purchase of hard hats or the running of sophisticated vapor dispersion computer simulations.

But the fundamental challenge for industry professionals runs deeper than this — it is to make sure that the concept of “Safety as a Value” does not fade away. As discussed in last week’s post this concept may have ethical and moral roots but it only became practicable as society created large amounts of net energy (money) in the early days of the Industrial Revolution. There is nothing that says that we cannot regress.

The Newness of Safety

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Child Labor

Child Labor

We are starting a new series at this blog. The theme is “Industrial Safety in an Age of Limits”. The series will be developed around the following parameters:

  1. In the modern industrial world safety is a value, but this value was adopted only as the Industrial Revolution gained traction. The concept of safety as a value is a cultural artifact — it can come and it can go.
  2. Exponential growth on a finite plant cannot continue; we are reaching limits. Non-renewable resources such as oil and water are disappearing and our capacity to absorb waste such as CO2 in the atmosphere and acid in the oceans is reaching a limit. We are coming to the end of a 300 year fossil fuel party.
  3. Progress is not inevitable — regress can happen. Over the course of the last 200 years or so there has been immense progress in improving industrial safety — but continued progress cannot be taken for granted. There is no law that says that safety cannot deterioriate.
  4. The fundamental challenge facing safety professionals in coming years will be to ensure that safety remains a value. In order to do they will need to learn about non-technical topics, particularly history and literature. Historical patterns do tend to repeat, if not exactly. “History does not repeat itself, but it does rhyme”.

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Safety Slogan

Safety Sign

Those who work in industry are repeatedly told that safety is the most important part of their work. Slogans such as the following are part of their mental furniture,

  • Safety a culture to live by.
  • Safety is a frame of mind – So concentrate on it – all the time.
  • Safety is not a job; it is a way of life.
  • . . . and so on.

Egyptian-Pyramid-Workers-2Slogans such as these are saying, “Safety is a Value” — indeed, it is the most important value of all. But we need to recognize that this has not always been the case, as the picture to the right shows. In it we see Egyptian laborers building the Pyramids; they are cutting stones, hauling them to a new location and then lifting them into place. In a modern safety culture we would expect these workers to be wearing as a minimum: safety shoes, safety glasses, hard hats, gloves and sturdy clothing. Instead they seem to be dressed in loin cloths, and little else. And it is doubtful that they were wearing sunscreen, in spite of the climate.

Safety as a Value

We take it for granted that safety in the workplace is a goal that does not have to be justified — it is its own justification. Safety is a value — the highest value. It’s an attitude that seems to be baked into our genes. We know that some work places are safe and some less so. We even understand that some managers are hypocritical, and merely talk a good game. But we never find a company where managers say, “Safety doesn’t matter.” Yet such an attitude was not always prevalent. The idea of safety as a value actually only came into existence at the start of the Industrial Revolution in the mid-18th century.

Frederick Douglass

Frederick Douglass

A similar shift in attitudes with regard to slavery took place at around the same time. Until the late 18th century slavery (or related systems such as serfdom and indenture) was a set feature of life in many countries. And yet, quite suddenly, it was challenged on moral grounds by visionaries such as William Wilberforce and Frederick Douglass.

Patrick Henry

Patrick Henry

Yet for all of the legitimate moral outrage to do with slavery prior to the industrial revolution many of the most enlightened people of the time held on to slavery — they could not see any alternative if they were to maintain their comfortable standard of living. For example, in the year 1773 Patrick Henry — “Give Me Liberty or Give Me Death” — wrote a letter to John Alsop, a member of the Society of Friends (Quakers).

Would any one believe that I am master of slaves by my own purchase? I am drawn along by the general inconvenience of living without them. I will not — I cannot justify it, however culpable my conduct.

We see the same lack of direct action on the part of Thomas Jefferson (1743-1826). He was a tireless advocate for freedom in general and was active in stopping the slave trade. But he never quite got around to running his own estate at Monticello, Virginia without slaves.

So why did safety and slavery become values during the course of the 19th century given that neither had been a priority in the thousands of years leading up to that time? It would be good to think that the industrialists and politicians of the day suddenly developed a moral and ethical awareness that had not been present in any human society heretofore. But the fact that these two systems were challenged at the time of the Industrial Revolution suggests that something else was going on — it would appear as if industrialization itself created an environment in which it was possible to see safety as a value. As for slavery, wealthy people such as Henry and Jefferson no longer needed human slaves — they could use machines to provide the cheap labor that they needed to maintain their life styles. And the same argument can be applied to the growth of safety as a value.

Of course, the Industrial Revolution brought with it its own horrible safety and health problems. One group of people who helped improve working conditions were authors such as Charles Dickens (1812-1870). For example, with regard to the fictional Coketown he writes,

They [ the industrialists ] were ruined when they were required to send labouring children to school; they were ruined when inspectors were appointed to look into their works; they were ruined, when such inspectors considered it doubtful whether they were quite justified in chopping people up with their machinery; they were utterly undone, when it was hinted that perhaps they need not always make quite so much smoke . . .

Here is his satirical description of the manner in which the poor were treated,

. . . they established the rule that all poor people should have the alternative (for they would compel nobody, not they) of being starved by a gradual process in the house, or by a quick one out of it. With this view, they contracted with the waterworks to lay on an unlimited supply of water, and with a corn-factor to supply periodically small quantities of oatmeal, and issued three meals of thin gruel a day, with an onion twice a week and half a roll on Sundays. They made a great many other wise and humane regulations . . .

Gradually the situation started to improve. For example, the industrial revolution was powered by the steam engine. Boiler explosions occurred  frequently, but when they did the response was local — there was no overall systematic study as to how to prevent such explosions. By the start of the 20th century the number of industrial accidents had risen to unacceptably high levels. For example, between the years 1870 and 1910 at least 10,000 boiler explosions occurred in North America; by 1910 the rate was 1,300 to 1,400 per annum. In response to this unacceptable situation the newly formed American Society of Mechanical Engineers (ASME) published its first boiler code in the year 1914.

Boiler-Explosion-1

Boiler Explosion

Economics of Safety

The above discussion suggests that safety is a cultural artifact that becomes a value only when there are sufficient economic resources available. If this is the case then there are three ways in which this support occurs.

  1. The technology for safety equipment becomes available.
  2. Safety becomes affordable; the goods produced by the machines created a surplus that allowed new activities, including safety, to be funded.
  3. Safety becomes its own economic justification — a facility that is safe is also profitable.

Technology for Safety

The first of the economic shifts discussed above — technology for safety equipment — is more or less self-evident So, the reason that Egyptian pyramid builders did not use hard hats was that hard hats had not been invented.

The picture below shows a factory in England (it is taken from a promotional video published in the year 1954). The men are pouring steel into molds. None of them are wearing any type of Personal Protective Equipment (PPE) and many of them have their shirt sleeves rolled up.

Pouring Steel

Pouring Steel

It is easy to criticize this group of men and the management of the company that they worked for. But many of the PPE items that we take for granted now were not available then. For example, the plastics used in modern safety glasses had not been invented. The only safety glasses that they could use had lenses made of reinforced/toughened glass. They were heavy and not all that effective.

Safety Becomes Affordable

The second observation that we can make with regard to changes in safety in the last 250 years is that it has become more affordable. A key feature of industrial society is that it produces a surplus of all kinds of goods. Some of this surplus can be directed toward buying safety equipment and improving safety services, including sophisticated computerized simulations of issues such as fires, explosions and vapor releases and developing codes and standards.

Economic Justification

The third reason for improving safety standards is based on the philosophy that a safe system is also a productive system. If a company can manage safety well then it has in place the systems to manage everything else well.

Reversal of the Value

The above discussion has demonstrated that safety is a cultural artifact and that it was technological advances that provided a means whereby safety could be elevated as a value. But this means that we must address the possibility of the opposite situation occurring; as technological productivity starts to slip due to the resource limitations that we face, so there could be reversion to a time when safety was not a value. So, for example, it is likely that it will not be as easy to obtain money and other resources for safety improvements as it was in the past. Increasingly engineers and safety professionals will be challenged to provide an economic justification for the changes that they want to make. They will also have to show that the proposed action makes economic sense and that it is achievable with current levels of technology.

The fundamental challenge that will face professionals will be to ensure that, in spite of all the changes that are likely to occur, we do not revert to a situation such as that shown in the picture below.

Mine Labor

Mine Labor