McGhee v National Coal Board

Where an employer negligently omits a precaution that would materially reduce the risk of an industrial disease, and the employee contracts the disease within that risk, causation may be established although medical science cannot say that the precaution would probably have prevented it. In this class of case, a material increase in risk may constitute a material contribution to the injury.

The negligent factor need not be the sole cause or independently sufficient. It must make a substantial or non-negligible contribution. The claimant must prove the relevant breach, increase in risk and resulting disease on the balance of probabilities, but need not demonstrate a medically irrefragable chain of causation.

In McGhee v National Coal Board [1973] 1 WLR 1, a labourer contracted dermatitis after working in exceptionally hot and dusty brick kilns. The Lord Ordinary found that the disease was occupational and that the employers had negligently failed to provide shower baths. He nevertheless assoilzied the employers because the medical evidence could not establish that showers would probably have prevented the disease.

The First Division refused the employee's reclaiming motion. On appeal to the House of Lords, the principal issue was whether proof that the omission materially increased the risk of dermatitis was sufficient to establish that the breach caused or materially contributed to the disease. A separate allegation that the kilns should have been cooled further also remained in issue.

1. Disposition. The House of Lords unanimously allowed the appeal. The employee had established that the admitted failure to provide shower baths materially contributed to the dermatitis, although medical science could not identify the precise biological mechanism.
2. Cooling of the kiln. Per Lord Reid, Lord Simon of Glaisdale, Lord Kilbrandon and Lord Salmon, the allegation that the kiln should have been cooled further failed. The required degree of cooling had not been specified, and the evidence did not establish that dispensing with the fan, preventing sweating or delaying entry was reasonably practicable. The hot and dusty working conditions were therefore not themselves proved negligent.
3. Washing facilities. The finding that adequate showers should have been provided was accepted before the House. Per Lord Wilberforce and Lord Salmon, immediate washing was the only practicable precaution capable of removing the remaining dust and materially reducing the recognised risk of dermatitis. Lord Reid found that abrasion could continue while the employee cycled home covered in sweat and grime.
4. Causation. Per Lord Reid, a claimant succeeds where the defendant's fault caused or materially contributed to the injury. The faulty factor need not have been sufficient by itself. From a broad and practical viewpoint, no substantial distinction could be drawn in this case between materially increasing the risk of dermatitis and materially contributing to its occurrence.
5. Lord Wilberforce reasoned that where a breach creates a risk and injury occurs within that risk, the creator of the risk should bear the loss unless another cause is shown. Medical inability to segregate the effects of compound causes should not place an impossible evidential burden on the injured employee. Lord Simon considered that cumulative factors could operate concurrently or successively and that a material reduction in risk was, in this type of case, the counterpart of a substantial contribution to injury.
6. Lord Kilbrandon concluded that the employee was required to establish a probability, not an irrefragable medical chain. Lord Salmon likewise treated causation as a practical question of fact and held that, as a rule, an employer whose negligence materially increases the risk of an industrial disease is liable when the employee contracts it. The reasoning in Wardlaw v Bonnington Castings 1956 S.C. (H.L.) 26 and Nicholson v Atlas Steel Foundry and Engineering Co. 1957 S.C. (H.L.) 44 supported that conclusion.

1. House of Lords: In McGhee v National Coal Board [1973] 1 WLR 1, the House unanimously allowed the employee's appeal. It held that the failure to provide showers had materially contributed to the dermatitis.
2. First Division of the Court of Session: On 17 March 1972, the court adhered to the Lord Ordinary's interlocutor and refused the employee's reclaiming motion.
3. Lord Ordinary: Following proof before answer, Lord Kissen found that the dermatitis was occupational and that failure to provide showers was negligent. He assoilzied the employers because causal connection between that breach and the disease had not been established on the balance of probabilities.