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Wilkinson Coutts & Matthews Integrity Training

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WILKINSON COUTTS / MATTHEWS INTEGRITY HUB: an up-to-the-minute information mix designed to help you with your lifework and career development in the asset integrity, inspection and NDE industries.

Matthew Petroleum Notes

Plant Integrity: Are you breaking the law?

The Law

About laws

Like all other laws, those relating to plant mechanical integrity can get a bit complicated. In general, there are more laws relating to the safety of plant items than their integrity alone. This makes sense as laws are predominantly there to protect people rather than inanimate things. The first thing to consider is that laws are the product of individual countries and states, not of society at large. Hence the laws that apply to you depend on which country you are in. They vary from being well-structured, to old-fashioned, prescriptive, goal-seeking, oppressive, liberal, haphazard or almost non-existent, depending on where you happen to be so there is no general guidance that will apply to all.

Health and safety take priority

In most countries, enforcing authorities see plant integrity as meaning safety, and not much else. Their inspection and enforcement system is set up with the prime aim of protecting people from the risk of serious injury. This is achieved by a mix of regulations covering types and designs of engineering plant and how it is operated. These will generally come as an overlapping set of separate regulations, to allow for the complexity of industrial systems, what they do, and how they work.

Pressure systems legislationThe Fig shows the situation in the UK, taking pressure equipment as an example

Breaking the law

Simplistically, all you have to do to break the law is to do something with engineering plant (manufacture it, operate it, repair it, or whatever) in a way that results in a risk of serious injury to people. Simple as that. Some caveats that apply to this risk that you create are:

  • It must be foreseeable
  • It must be greater than a predetermined level of benchmark risk that has been decided and incorporated into statutory regulations(without consulting you, sadly)

Notice that there is no requirement for there to have actually already been an accident as a result of what you were, or weren’t, doing; creating a risk is enough in itself. There are other ways to break laws, for example by not complying with some administrative requirement, but the consequences are generally less.


Risk = Probability x Consequence

This definition of risk is fairly well accepted by most countries and legal jurisdictions. It gives a way of deciding how large a risk actually is. As an example, whereas the consequence of a re-entering space rocket landing on your house would be catastrophic (high consequence), the probability (likelihood) of it actually happening would be infinitesimally small. Hence the overall risk (probability x consequence) would be small; probably small enough to not be foreseeable.

This Probability x Consequence metric is used in many aspects of plant inspection and integrity evaluation, not just those relating to legal compliance. It goes under several names, risk-based inspection (RBI), risk-based maintenance (RBM) being common ones. It also exists in more hidden form in other areas such as plant repairs, Integrity Operating Windows (IOWs) and FFP (fitness-for-purpose) evaluations. If you want to remain in compliance with regulations, and safe, it is wise not to ignore it. You may be surprised how many people and companies do.

For a better explanation of risk as it influences legal compliance, see our linked article on risk foreseeability and benchmarks

How does the UK HSE enforce H&S legislation? See our linked article Do you feel lucky ?

WE ARE PARTICULARLY INTERESTED in hearing about failures caused by fatigue, brittle fracture, rogue materials, operator error, non-code compliant design, poor site repairs and unauthorised modifications to equipment. See our Failure Briefings page if you are interested in participating

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Tel: 07746 771592