Understanding ‘reasonably foreseeable’ risk in health and safety

Written on 7 December 2021

Health and safety negligence-based law provides that employers have a duty to prevent injury or harm from acts that are “reasonably foreseeable”. As an employer, this means you’re expected to be able to identify and manage reasonably foreseeable risks at work.

In short, workplace risks are not expected to be managed if they couldn’t have been identified or understood beforehand. However, employers are expected to identify and appropriately manage those risks created by your work activities that can be anticipated. In most instances, these are the risks that a competent person working in your particular field would be able to predict or expect harm from. There are also some instances where the at-work risks would only be recognised by a competent technical expert. 

The famous 1932 Donoghue v Stevens negligence case (in which a consumer sued a drinks manufacturer after discovering a dead snail inside a bottle of ginger beer) makes the concept of foreseeability seem relatively straightforward. In it, the judge claimed that “liability can only arise where a reasonable man would have foreseen and could have avoided the consequences of his act or omission”.

Unfortunately, there are problems with this simple statement. If you engage in a business activity, you’re expected to be able to foresee more than the “reasonable man” in relation to that activity. For example, while a reasonable member of the public may know little about Legionella, a facilities manager should be aware of its potentially to cause harm. Beyond this, an environmental consultant should have additional expert knowledge to foresee possibilities that the facilities manager would not have thought of.

Three tests are therefore used to decide whether a risk is reasonably foreseeable, namely common knowledge, industry knowledge and expert knowledge. In most workplaces, you will be expected to identify and manage those risks that require common and industry knowledge. If you’re an expert, then you will additionally be expected to manage and identify risks requiring that expert knowledge.

Hindsight is 20/20

Work activities often expose people to risks that are unknown at the time. As knowledge and understanding increases, these risks become understood. For example, the serious ill-health effects of inhaling asbestos dust are understood today. Now, exposing a worker to asbestos is unacceptable because the risks are reasonably foreseeable. However, asbestos wasn’t recognised as a harmful substance in the 1950s. Accordingly, an employer would not then have been expected to manage asbestos risks, since they weren’t considered reasonably foreseeable at that time – it would of course be unfair to look back and retrospectively apply the required foresight.

On the other hand, an employer can expect to fall foul of negligence law if exposing workers to a risk that any reasonable person would identify and recognise as unacceptable. However, this might not be the case if the risk was of a highly technical nature – since it may be beyond the employer’s knowledge and understanding, even if they’re highly skilled and competent in their particular field. 

The law would, for example, take a dim view of an employer who put an untrained and unsupervised worker at the controls of a high-risk piece of machinery, such as a lathe. This is because a reasonable person would recognise the risk. On the other hand, an employer might not be at fault if a piece of machinery unpredictably fails after being used correctly and for its intended purpose – particularly if the fault is very rare or previously unheard of in the industry.  

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The three tests for reasonable foreseeability


Common knowledge

Most of us should be able to recognise common workplace hazards, and employers are therefore expected to control these more obvious risks. If a reasonable person would recognise the risk associated with the work by applying common sense/knowledge, then it’s reasonably foreseeable. An average person would, for example, recognise the risk associated with working on a tall building’s sloping roof.


Industry knowledge

If a particular risk is well-known and understood in an industry, it will be reasonably foreseeable. For example, the risk of operating unguarded moving machinery is commonly recognised in manufacturing. The risk might not be recognised by someone who doesn’t work in the industry, but it is still considered reasonably foreseeable. This is because employers and workers are expected to have a certain degree of industry knowledge.


Expert knowledge

If a risk is outside the knowledge of most competent people working in a particular industry, then it might not be reasonably foreseeable. Only experts are expected to identify such risks. For example, where a chemical isn’t classified as hazardous to health and isn’t generally recognised as harmful in a particular industry, then the health risks from workers being exposed to that chemical cannot be said to be reasonably foreseeable by your average employer – even though some research chemists might disagree if asked for their expert opinion.

As a real-life example of this, a fire risk assessor who provided an inadequate assessment for a residential block was recently fined and given a suspended sentence. Despite being an expert in fire safety, it emerged that he had not lifted ceiling tiles or even opened riser cupboard doors to check for fire safety risks at the three-storey building. The fact that such oversights were made despite their professional knowledge was a key factor in the case. The judge said: “The job of a fire risk assessor is a highly responsible one. Lives are in their hand and their judgement is critical.”

Ultimately, employers are normally expected to identify and manage reasonably foreseeable risks – in other words, those recognised by a reasonable person and by competent people working in their industry. Here, the common knowledge and industry knowledge tests apply. Employers will rarely be expected to identify and manage those risks that would only be recognised by experts – unless they themselves are an expert, in which case, the expert knowledge test also applies. 

Curious cases of reasonable forseeability

Whether an action was reasonably foreseeable has been much discussed by the courts. In the 1951 case of Bolton v Stone, a woman was struck by a wayward cricket ball while in her garden. She brought a negligence action against the cricket club neighbour. The claim ultimately failed as necessary precautions were in place, namely a 17-foot-high boundary fence. It was also agreed that the batsman’s shot was altogether exceptional. Nothing like it had been seen in the 70 years that cricket had been played there; a ball had never before cleared the ground. Accordingly, the likelihood of harm was not foreseeable by a reasonable person. There would be negligence involved if cricket balls were regularly hit out of the ground, since it would be reasonably foreseeable that this action may lead to serious injury. Indeed, this was the judgment in an earlier case of Castle v St Augustine’s Links in 1922.

Importantly, the reasonable foreseeability rule developed in these common law negligence cases underpins health and safety legislation, and applies to employers on an everyday basis, for example where an employer does not provide suitable training or protective clothing to employees – here, a reasonable person would anticipate that an accident may occur. The employer would be negligent in such circumstances. Interestingly, the sentencing guidelines for health and safety offences make clear that people must be protected from their own “neglectful” behaviour if it is reasonably foreseeable – an example might be not wearing personal protective equipment.

There are exceptions to the reasonable foreseeability rule. In some instances, while the likelihood of harm may be seen as so low that it otherwise wouldn’t be considered, the seriousness of the harm may be seen as so severe that it supersedes the low likelihood – the harm must therefore be viewed as if it was reasonably foreseeable. This happened in the cases of Wagon Mound No.2  in 1967 and Paris v Stepney in 1951. Therefore, if the activity you are carrying out could potentially have serious implications, then this risk cannot be ignored – no matter how slim the chance of something potentially serious happening is.

The health and safety sentencing guidelines also further indicate how the courts assess foreseeability: “Failure to heed warnings or advice from the authorities, employees or others or to respond appropriately to ‘near misses’ arising in similar circumstances may be factors indicating greater foreseeability”. For this reason, those who ignore opportunities to remedy unsafe conditions or practices despite being aware of them – such the car salvage firm boss who was recently jailed for 15 years for ignoring HSE notes – are likely to be judged more harshly should an incident occur.

Get peace of mind the WorkNest

From a programme of audits to practical advice, WorkNest assigns named Health & Safety specialists to help organisations take a proactive approach to risk management, meet their legal obligations, and greatly reduce the potential for health and safety incidents. With our support, you can be sure that foreseeable risks are identified and properly controlled so that your team can work safely and your business isn’t exposed.

To find out more about our personalised, fixed-fee Health & Safety services, call 0345 226 8393 or request your free consultation using the button below.

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