Volex Group Plc v Evans

Liability for illness allegedly caused by workplace fumes requires proof that the claimant was exposed to dangerous levels of a toxic substance and that the exposure caused the illness. Where agreed medical evidence makes causation conditional on that exposure, the court cannot infer toxic exposure merely from the presence of fumes and the subsequent illness. This remains so where the obvious potential toxic substances have been excluded. Without proof of the relevant chemical exposure, any failure to remove the claimant from the workplace cannot establish causation.

The claimant worked in a factory where a nearby machine emitted acrid fumes during her shift. She later developed respiratory and psychiatric problems. The pleaded statutory-duty case under the Control of Substances Hazardous to Health Regulations 1994 was abandoned because the alleged chemicals were not shown to have caused injury. The High Court nevertheless found that the fumes caused the claimant’s initial illness and found negligence in failing to remove her from the area earlier. The employer appealed, challenging the inference of toxic exposure and causation.

Sir Christopher Staughton delivered the leading judgment. Chadwick LJ and Schiemann LJ agreed that the appeal should be allowed.

1. The claimant had to establish exposure to dangerous levels of toxic fumes. The evidence did not identify any chemical reaction or toxic substance capable of causing her illness. The more obvious potential sources, including hydrogen chloride, phosgene and phenol, had been ruled out.
2. The agreed medical evidence was decisive. It stated that, if the court was not satisfied that the claimant had been exposed to dangerous levels of toxic fumes, her initial illness was probably infectious. The judge’s inference that the illness itself made toxic exposure likely amounted to impermissible a priori reasoning and undermined the agreed evidential position.
3. It was not open to the judge, on the evidence, to infer negligence from an unidentified toxic element in the fumes. The claimant had not shown that her illness was caused by exposure to dangerous fumes.
4. Since toxic exposure and causation were preconditions to liability, the court did not need to determine whether the employer had been negligent in failing to insist that the claimant leave the machine. In any event, there was no evidence that remaining at the machine caused or aggravated a viral illness.

The appeal was allowed, the action was dismissed, and the respondent was ordered to pay the costs of the appeal and of the action below, subject to detailed assessment if not agreed.

1. Court of Appeal (Civil Division): the appeal was allowed and the action dismissed: [2002] EWCA Civ 225.
2. High Court of Justice: before Elias J, the claimant’s illness was found to have been caused by the fumes, with negligence found in failing to remove her from the workplace. The employer obtained permission to appeal.