The word “stop” has one meaning. To cease an activity. When you drive along the road and a traffic  light turns red, you respond to two things. The instruction to bring the vehicle to a standstill, and the presence of danger of other traffic being allowed to drive. These things, called “initiators” are based on your life experience, training and knowledge. You know from your training as a driver what the red light means. You also learn from experience that failing to stop causes a collision, or at least a financial penalty in the form of a fine. That is why most people do “stop” at a red traffic light.

Yet all too often the “Stop” signs are ignored. Stop Smoking is one of the most common examples where “stop” is ignored. And the reason is a lack of the second initiator. There is no immediate danger that puts a sense of urgency in your actions.

But there are also other factors that influence Stop. One is choice. Choice is a mental process that allows us to decide on a course of action based on available information. This information can be knowledge, training, experience or judgement, referred to as your frame of reference. An individual’s frame of reference is a mental encyclopedia from where information is drawn in order to make a choice between two options or more. The extent of our frame of reference determine our ability to make a rational choice. Rationality is the process of measuring up the various options within a given scenario and taking the “preferred” route of action or in-action. The preferred route is driven by “motive”.

So when approaching a red traffic light, we apply our frame of reference and take our preferred action. A driver who jumps the light, made a different choice than the one who stopped. And the former is not conforming to the norm or standard practice.

In the workplace, it is pretty much the same process that occurs. A worker’s actions are determined by their frame of reference.

An employee working in the printing industry lost his index finger in a guillotine. The guillotine is operated by pressing two push-button switches on either side of the machine bed, to ensure the operator’s hands are outside the danger zone. An infra-red beam indicated the cutline on the paper allowing the operator to move it around until it is aligned to the markings on the paper. Additional infra-red beams stops the guillotine blade if they are broken by an intruding object such as the operator’s hands or arms. How did the operator lose his finger?

The operator was trained, had 12 years experience and have been subjected to a variety of safety training courses over the years. But he decided to alter the path of operation by jamming a tooth pick into the one push button. This allowed him to adjust the paper to be cut, while pushing the only working push-button with his free hand. In the process, he managed to increase his production out-put and outperform his co-workers. He was doing fine until the day the beams malfunctioned. As he relied on the beams to protect him should he make a mistake, he pressed the button while he was holding the paper down in the desired position, but mis-aligned his index finger and lost it when the blade came down.

In a similar scenario, a driver approached the red traffic light, saw no cars in the intersection and decided to jump the light, colliding with a truck he did not see approaching from the right due to the building on the corner. A combination of excessive speed and a deliberate decision to jump the light are the basic human causes. He was not available for questioning after the collision, as he died on the scene; decapitated by the chassis of the much higher truck.

These and similar incidents are proof that there is a definitive sequence in accident causation and there are multiple aspects to the human decision tree that influence our actions.

A standard traffic light works on timed intervals. There is a “loop” under the road surface that alters the sequence of the lights with every vehicle passing over it. If there is a sufficient delay between vehicles, the timed interval remains uninterrupted and the primary switch is triggered. The light switches to orange (amber or yellow). Two seconds later, the red goes on, and three seconds later, the opposite traffic light turns green, allowing a margin of safety where all vehicles in the intersection is standing still. The time intervals are based on the travel speed of the road. For a suburban road, a three second margin between crossing lights, is regarded as adequate to allow you to stop safely. The higher the travel speed, the longer the switch-over interval.

Just like complex traffic systems are based on pre-defined time-intervals, it is also based on the assumption that 80% of road users obey the signals, leaving a 20% chance of disobedience and allowing for the “insertion” of a countermeasure in the 3 second safety margin.

‘A common characteristic of many high-accident locations is that they place large or unusual demands on the information-processing capabilities of drivers. Inefficient operation and accidents usually occur where the chance for information-handling errors is high. At locations where the design is deficient, the possibility of error and inappropriate driver performance increases.’

Contrary to traffic systems, HSE systems are not designed to include these information-handling errors.

Development in HSE Systems

Transportation is as old as man-kind, from the first donkey cart to the Model-T and the latest introduction of the Self-driving car and fortunately, traffic design systems has kept up with changes.

Sadly, the same cannot be said for Health & Safety systems. We still cling to an accident causation approach created in 1941 by Heinrich and adapted and molded into different forms by Krause, Du Pont and Difford, but we forget to take into consideration the change of the modern person. We are no longer operating donkey cars. We are operating Google cars; or not. The occupational landscape has changed. We are no longer distracted by voices over a public address system. We are distracted by ring tones from mobile devices. We are no longer doing or jobs we used to 50 years ago. In fact, if your PC crash now, you won’t be able to do your job at all. That was not the case 30 years ago.

Yet, when we design HSE systems, we still focus on archeological concepts. STOP!

We can change from dominoes (Heinrich 1941) to cheese (Reason 1997), but what are we achieving?

Are we improving our HSE systems or merely the measurements we use? Are we still measuring the same distance with different units? Have we merely switched from inches to centimetres to determine the length of a piece of string?

The repetitive strain

Lightning does not strike the same place twice is a adage that actually means misfortune does not occur twice in the same way to the same person. It was not meant to be taken literally, and science has proven it wrong already. Yet when it comes to the Root Cause analysis theory, it is assumed that if the root cause is eliminated the accident will in all probability never occur again. Yet, lightning still strikes and accidents still happen.

It boils down to Murphy’s Law

If something can go wrong, it will. Analysing accidents using cheese or dominoes is only important in the realm of health & safety practice. It is designed to keep these practitioners busy. And no-one will stand up and admit that H&S systems do NOT prevent accidents. It is however a FACT. HSE systems do not prevent accidents. People do.

Who wants to die today?

I asked a group of employees once. I had no volunteers. Yet, every day, someone dies at work. And they did not volunteer for it either. It just happens. It happens in the most dangerous industries and it happens in companies with the highest possible safety grading. An employee can work for the same company using the same H&S System for any number of years and still meet with a fatal accident. It is the circle of life.

The cause of an accident is irrelevant to other accidents

Preventing the root cause of one accident is not a means to prevent a similar accident. In fact, a similar accident will never occur again, ever. An accident is like a finger print. No two is exactly the same. Two drivers jumping the red light did not follow the same decision tree to decide on their actions. Why then waste hours on investigations?

The accident investigation process takes two approaches in general, as Slater noted in his report “Rooting out the cause” (2012) that being the multi-cause theory and the single cause theory. In both philosophies, barriers are created to counter the occurrence of incidents in the shape of the hierarchy of controls and both investigative techniques seeks to identify the cause(s) and assign it to a chain of events attributed to the “company” or “management”.

No wonder management have given up on HSE. After years of seeing the same statistics, reading the same format of incident reports and spending the same amount of money on the same “legal requirements”, it becomes as boring as a pendulum.

Bird’s Ratio misused

Herbert Heinrich’s research (1931) and Bird’s further research (1969) on causes of accidents resulted in the almost religiously followed ratio of 88-10-2, where 88% of accidents are human error, 10% is unsafe conditions and 2% are acts of providence (Acts of God).

Subsequently, the Causation (Safety) Pyramid, grouping accidents by severity, resulted in a debate on near-miss / hit accidents and the investigation of near miss accidents to determine their route causes has become a major part of the H&S practioner’s job function in the name of improvement.

Advancement of the 10%

According to Bird, only 10% of accidents are caused by unsafe conditions and/or machines, yet more has been done on the improvement of this, than on the 88%, raising further doubt as to the impact of HSE systems on the global reduction rate of workplace injuries.

One cannot help to wonder what the result would be of a repeat study, similar to the research performed by Heinrich, back in 1931. Take cars for instance. A 1910 Model-T ford has more safety issues than revolutions per minute, but in 1910 that was “state of the art” motoring. The introduction of computerised systems such as SCADA back in the 1960’s reduced machine operation failures through proper condition monitoring systems, leading the way toward fully automated machine systems where humans only need to touch a screen to perform an action.

Applying thinking based on the Pareto Principle, that 80% of results are derived from 20% of actions, the HSE system’s claim to success in accident reduction over the past 5 decades are minimised in comparison.

The change impact of advancement in operator interaction systems or Human Machine Interaction(HMI) has introduced new hazards, almost “blood free” in that fatalities and amputations have been replaced by musculo-skeletal impairment, ergonomic factors and an increase in stress-levels. Yet the 88% has never altered its way of thinking.

“Safer” and “Better” chemical substances have been introduced over the years, which have increased other health hazards over long term exposure. Take the dry-cleaning industry as example, where historically, benzene was used. This was later replaced with other substances, each presenting a new hazard to the workplace.

A more active role for the 2% – Occupational Health

The acts of God, which commonly describe accidents which were not caused by humans or man-made objects, may have increased its role in the workplace and become more active as a “cause donor”. Illnesses and disorders identified over the past 5 decades have not been subjected to occupational health related research nor have they been included in the Heinrich or Bird’s research, as these were based on “insurance claims” for physical damages or losses.

One case in point where Safety statistics such as Bird’s safety pyramid becomes invalid is the 1979 outbreak of Anthrax when the town of Sverdlovsk (now Ekaterinburg) in the then-Soviet Union was exposed to an anthrax leak from a nearby bio-weapons facility. It is thought that the accident caused the infection of at least 94 people, 68 of whom died. An extensive cover-up operation was undertaken before Russian President Boris Yeltsin eventually admitted to the disaster in 1992.

Another is Asbestosis and its related Mesothelioma. The disease, which can take between 20 and 50 years to appear, is identified by various symptoms, including chest pain, fatigue, neck or facial swelling, and in severe cases blood clots, jaundice and internal bleeding. The dangers of exposure to asbestos were identified in the early 20th century, but this did not prevent the ongoing risk of mesothelioma to workers around the world. In Western Australia, the deaths of over 500 people from the disease appear to be linked with asbestos mining that took place between 1945 and 1966. And in recent years – from 1980 to the late 1990s – the number of people dying from the disease went up from 2,000 a year to 3,000 in the US alone. Many buildings built before asbestos was banned may contain it, and renovators and builders should proceed with caution.

The influence of Raynaud’s disease and others on the Bird pyramid

Vibration delivered to the hand and arm by industrial pneumatic tools is a common cause of vascular and neurovascular problems, including cold-induced vascular spasm (vibration white finger) and peripheral neuropathies with paresthesias, dysesthesias, and sensory abnormalities. A decade ago, the US Public Health Service estimated that 1.2 million American workers were at risk. Differentiation of primary and secondary Raynaud’s phenomenon from the thoracic outlet syndrome and from the carpal tunnel syndrome pose potential diagnostic difficulties. Despite growing public recognition of upper extremity problems caused by repetitive trauma, there have been few investigations of vibration-induced disorders in the United States. This is not true worldwide, particularly in Northern Europe, where there has been significant intervention in medical surveillance and tool design. There does appear to be, however, frequent misdiagnosis and misdirected surgery. This has particular significance for the clinician, since in the 1990s, cumulative trauma injuries are expected to exceed all other work-related injuries.

Disputed but not refuted?

Many supporters of the Bird Pyramid claims that it may be disputed but has not been refuted. This may be the case, but based on the origins and scope of the research, the impacts of the various changes in the occupational landscape and the inclusion of occupational health in the HSE profession, the Pyramid no longer deserves a place in the current world.

The fact of the matter is that HSE research and knowledge is fragmented across different professions, from Safety engineering to neurology, and there is no common system to determine the cause of incidents in the modern workplace.

The final question then remains. Why are we still using accident causation in HSE?