Posts Tagged ‘Safety’

The picture is of Elisha Graves Otis demonstrating, in the mid 19th century, his safe elevator that automatically applies a brake if the lift cable breaks. It is a “simple” fail-safe mechanical design that effectively created the elevator industry and the opportunity of high-rise buildings.

“To err is human” and human factors research into how we err has revealed two parts – the Error of Intention (poor decision) and the Error of Execution (poor delivery) – often referred to as “mistakes” and “slips”.

Most of the time we act unconsciously using well practiced skills that work because most of our tasks are predictable; walking, driving a car etc.

The caveman wetware between our ears has evolved to delegate this uninteresting and predictable work to different parts of the sub-conscious brain and this design frees us to concentrate our conscious attention on other things.

So, if something happens that is unexpected we may not be aware of it and we may make a slip without noticing. This is one way that process variation can lead to low quality – and these are the often the most insidious slips because they go unnoticed.

It is these unintended errors that we need to eliminate using safe process design.

There are two ways – by designing processes to reduce the opportunity for mistakes (i.e. improve our decision making); and then to avoid slips by designing the subsequent process to be predictable and therefore suitable for delegation.

Finally, we need to add a mechanism to automatically alert us of any slips and to protect us from their consequences by failing-safe.  The sign of good process design is that it becomes invisible – we are not aware of it because it works at the sub-conscious level.

As soon as we become aware of the design we have either made a slip – or the design is poor.


Suppose we walk up to a door and we are faced with a flat metal plate – this “says” to us that we need to “push” the door to open it – it is unambiguous design and we do not need to invoke consciousness to make a push-or-pull decision.  The technical term for this is an “affordance”.

In contrast a door handle is an ambiguous design – it may require a push or a pull – and we either need to look for other clues or conduct a suck-it-and-see experiment. Either way we need to switch our conscious attention to the task – which means we have to switch it away from something else. It is those conscious interruptions that cause us irritation and can spawn other, possibly much bigger, slips and mistakes.

Safe systems require safe processes – and safe processes mean fewer mistakes and fewer slips. We can reduce slips through good design and relentless improvement.

A simple and effective tool for this is The 4N Chart® – specifically the “niggle” quadrant.

Whenever we are interrupted by a poorly designed process we experience a niggle – and by recording what, where and when those niggles occur we can quickly focus our consciousness on the opportunity for improvement. One requirement to do this is the expectation and the discipline to record niggles – not necessarily to fix them immediately – but just to record them and to review them later.

In his book “Chasing the Rabbit” Steven Spear describes two examples of world class safety: the US Nuclear Submarine Programme and Alcoa, an aluminium producer.  Both are potentially dangerous activities and, in both examples, their world class safety record came from setting the expectation that all niggles are recorded and acted upon – using a simple, effective and efficient niggle-busting process.

In stark and worrying contrast, high-volume high-risk activities such as health care remain unsafe not because there is no incident reporting process – but because the design of the report-and-review process is both ineffective and inefficient and so is not used.

The risk of avoidable death in a modern hospital is quoted at around 1:300 – if our risk of dying in an elevator were that high we would take the stairs!  This worrying statistic is to be expected though – because if we lack the organisational capability to design a safe health care delivery process then we will lack the organisational capability to design a safe improvement process too.

Our skill gap is clear – we need to learn how to improve process safety-by-design.


Download Design for Patient Safety report written by the Design Council.

Other good examples are the WHO Safer Surgery Checklist, and the story behind this is told in Dr Atul Gawande’s Checklist Manifesto.

Many believe that a queue is a good thing.

To a supplier a queue is tangible evidence that there is demand for their product or service and reassurance that their resources will not sit idle, waiting for work and consuming profit rather than creating it.  To a customer a queue is tangible evidence that the product or service is in demand and therefore must be worth having. They may have to wait but the wait will be worth it.  Both suppliers and customers unconsciously collude in the Great Deception and even give it a name – “The Law of Supply and Demand”. By doing so they unwittingly open the door for charlatans and tricksters who deliberately create and maintain queues to make themselves appear more worthy or efficient than they really are.

Even though we all know this intuitively we seem unable to do anything about it. “That is just the way it is” we say with a shrug of resignation. But it does not have to be so – there is a path out of this dead end.

Let us look at this problem from a different perspective. Is a product actually any better because we have waited to get it? No. A longer wait does not increase the quality of the product or service and may indeed impair it.  So, if  a queue does not increase quality does it reduce the cost?  The answer again is “No”. A queue always increases the cost and often in many ways.  Exactly how much the cost increases by depends on what is on the queue, where the queue is, and how long it is. This may sound counter-intitutive and didactic so I need to explain in a bit more detail the reason this statement is an inevitable consequence of the Laws of Physics.

Suppose the queue comprises perishable goods; goods that require constant maintenance; goods that command a fixed price when they leave the queue; goods that are required to be held in a container of limited capacity with fixed overhead costs (i.e. costs that are fixed irrespective of how full the container is).  Patients in a hospital or passengers on an aeroplane are typical examples because the patient/passenger is deprived of their ability to look after themselves; they are totally dependent on others for supplying all their basic needs; and they are perishable in the sense that a patient cannot wait forever for treatment and an aeroplane cannot fly around forever waiting to land. A queue of patients waiting to leave hospital or an aeroplane full of passsengers circling to land at an airport represents an expensive queue – the queue has a cost – and the bigger the queue is and the longer it persists the greater the cost.

So how does a queue form in the first place? The answer is: when the flow in exceeds the flow out. The instant that happens the queue starts to grow bigger.  When flow in is less than flow out the queue is getting smaller – but we cannot have a negative queue – so when the flow out exceeds the flow in AND the size of the queue reaches zero the system suddenly changes behaviour – the work dries up and the resources become idle.  This creates a different cost – the cost of idle resources consuming money but not producing revenue. So a queue/work costs and no queue/no work costs too.  The least cost situation is when the work arrives at exactly the same rate that it can be done: there is no waiting by anyone – no queue and no idle resources.  Note however that this does not imply that the work has to arrive at a constant rate – only that rate at which the work arrives matches the rate at which it is done – it is the difference between the two that should be zero at all times. And where we have several steps – the flow must be the same through all steps of the stream at all times.  Remember the second condition for minimum cost – the size of the queue must be zero as well – this is the zero inventory goal of the “perfect process”.

So, if any deviation from this perfect balance of flow creates some form of cost, why do we ever tolerate queues? The reason is that the perfect world above implies that it is possible to predict the flow in and the flow out with complete accuracy and reliabilty.  We all know from experience that this is impossible: there is always some degree of  natural variation which is unpredictable and which we often call “noise” or “chaos”. For that single reason the lowest cost (not zero cost) situation is when there is just enough breathing space for a queue to wax and wane – smoothing out the unpredictable variation between inflow and outflow. This healthy queue is called a buffer.

The less “noise” the less breathing space is needed and the closer you can get to zero queue cost.

So, given this logical explanation it might surprise you to learn that most of the flow variation we observe in real processes is neither natural nor unpredictable – we deliberately and persistently inject predictable flow variation into our processes.  This unnatural variation is created by own policies – for example, accumulating DIY jobs until there are enough to justify doing them.   The reason we do this is because we have been bamboozled into believing it is a good thing for the financial health of our system. We have been beguiled by the accountants – the Money Magicians.  Actually that is not precise enough – the accountants themselves  are the innocent messengers – the deception comes from the Accounting Policies.  The major niggle is one convention that has become ossified into Accounting Practice – the convention that a queue of work waiting to be finished or sold represents an asset – sort of frozen-for-now-cash that can be thawed out or “liquidated” when the product is sold.  This convention is not incorrect it is just incomplete because, as we have demonstrated, every queue incurs a cost.  In accountant-speak a cost is called a liability and unfortunately this queue-cost-liability is never included in the accounts and this makes a very, very, big difference to the outcome. To assess the financial health of an organisation at a point in time an accountant will use a balance sheet to subtract the liabilities from the assets and come up with a number that is called equity. If that number is zero or negative then the business is financially dead – the technical name is bankruptcy and no accountant likes to utter the B word.  Denial is not a reliable long term buisness strategy and if our Accounting Policies do not include the cost of the queue as a liability on the balance sheet then our finanical reports will be a distortion of reality and will present the business as healthier than it really is.  This is an Error of Omission and has grave negative consequences.  One of which is that it can create a sense of complacency, a blindness to the early warning signs of financial illness and reactive rather than proactive behaviour. The problem is compounded when a large and complex organisation is split into smaller, simpler mini-businesses that all suffer from the same financial blindspot. It becomes even more difficult to see the problem when everyone is making the same error of omission and when it is easier to blame someone else for the inevitable problems that ensue.

We all know from experience that prevention is better than cure and we also know that the future is not predictable with certainty: so in addition to prevention we need vigilence, prompt action, decisive action and appropriate action at the earliest detectable sign of a significant deterioration. Complacency is not a reliable long term survival strategy.

So what is the way forward? Dispense with the accountants? NO! You need them – they are very good at what they do – it is just that what they are doing is not exactly what we all need them to be doing – and that is because the Accounting Policies that they diligently enforce are incomplete.  A safer strategy would be for us to set our accountants the task of learning how to count the cost of a queue and to include that in our internal finanical reporting. The quality of business decisions based on financial data will improve and that is good for everyone – the business, the customers and the reputation of the Accounting Profession. Win-win-win.

The question was “Is a queue and asset or a liability?” The answer is “Both”.

Later in his career, the famous artist William Heath-Robinson (1872-1944) created works of great ingenuity that showed complex inventions that were created to solve real everyday problems.  The genius of his work was that his held-together-with-string contraptions looked comically plausible. This genre of harmless mad-inventorism has endured, for example as the eccentric Wallace and Grommet characters.

The problem arises when this seat-of-the-pants incremental invent-patch-and-fix approach is applied to real systems – in particular a healthcare system. We end up with the same result – a Heath-Robinson contraption that is held together with Red Tape.

The complex bureaucracy both holds the system together and clogs up the working – and everyone knows it. It is not harmless though – it is expensive, slow and lethal.  How then do we remove the Red Tape to allow the machine to work more quickly, more safely and more affordably – without the whole contraption falling apart?

A good first step would be to stop adding yet more Red Tape. A sensible next step would be to learn how to make the Red Tap redundant before removing it. However, if we knew how to do that already we would not have let the Red Tapeworms infest our healthcare system in the first place!  This uncomfortable conclusion raises some questions …

What insight, knowledge and skill are we missing?
Where do we need to look to find the skills we lack?
Who knows how to safely eliminate the Red Tapeworms?
Can they teach the rest of us?
How long will it take us to learn and apply the knowledge?
Why might we justify continuing as we are?
Why might we want to maintain the status quo?
Why might we ignore the symptoms and not seek advice?
What are we scared of? Having to accept some humility?

That doesn’t sound like a large price to pay for improvement!