In defining "significant" the Health and Safety Executive (HSE) uses the word "trivial" to define its opposite: "Significant risks are those that are not trivial in nature" (www.hse.gov.uk/risk/faq.htm).
The word trivial does not appear in the legislation. However, it does occur in court judgements.
R v Chargot (2008) concerned an untrained dump truck driver who died when his vehicle overturned. The House of Lords ruling made it clear that "when the legislation refers to risks it is not contemplating risks that are trivial or fanciful-¦The law does not aim to create an environment that is entirely risk-free-¦ It is directed at situations where there is a material risk to safety and health, which any reasonable person would appreciate and take steps to guard against."
R v Electric Gate Services Ltd (2009) made reference to Lord Hope's use of "trivial". A nine-year-old boy had been crushed between an electric gate and a pillar as he reached through to press a button to open the gates. Electric Gate Services (EGS), which installed the gates, was prosecuted but at the initial trial, the judge directed the jury to return a not guilty verdict because the accessibility of the gate opening controls did not represent an "appreciable risk".
One of the confusions in interpreting 'trivial' is whether we are referring to the risk or the hazard
However, at the Court of Appeal, Lord Justice Dyson ruled that "the prosecution did not have to prove that the risk was appreciable or foreseeable. They had to prove that the risk was not fanciful and was more than trivial."
The Chargot and EGS judgments refer to the case of R v Porter (2008). James Porter was the headmaster of a private school where a three-year old child was taken to hospital after hitting his head when he jumped off some steps. The infant died in hospital -- not from the head injury, but from a hospital-acquired infection, MRSA.
A jury found Porter guilty of failing to ensure the child's safety, despite the judge's direction that "What you must decide is whether there was an unacceptable risk. The trivial risks of everyday life are not unacceptable. They are simply a fact of life, are they not?"
The conviction was quashed, with the appeal judge concluding that since children will jump, the risk did not meet the criteria for being more than trivial.
Lord Justice Moses explained "the absence of any previous accident in circumstances which occur day after day" might be grounds for considering a risk as "fanciful".
One of the confusions in interpreting "trivial" is whether we are referring to the risk or the hazard. The outcome of a child dying is certainly not a trivial severity, but in both Porter and EGS, before the event both parties would have considered the likelihood of that event as trivial. But while hundreds of children jump from steps every day and do not die, any child crushed by a moving gate will suffer harm.
The evidence from case law is that we cannot ignore trivial risks if they are only trivial because we think the likelihood is remote. They can be ignored only where the most likely worst outcome is trivial.
There are plenty of legal cases looking at serious outcomes with a low probability; there are few cases where the worst outcome was a bruise or a papercut, however likely. Where the outcome is not trivial, we need to document our rationale for deciding the triviality of the likelihood.
In N is for near-miss (IOSH Magazine March 2017, bit.ly/2w6u55r) we touched on the problem of how near-miss reporting systems can be overwhelmed with reports of trivial risks which an organisation cannot control.
To encourage productive reporting the emphasis should not be on "how likely was that near miss to become an accident?" but on "if that near miss had been an accident, what is the worst that could have happened?"
Then it becomes easier to choose between reporting the "I bumped into an obstacle in the office, and the worst that could have happened is a bruise" and "I bumped into an obstacle in the corridor, and the worst that could have happened is that people were prevented from escaping in a fire".