Regina v Associated Octel Co Ltd; House of Lords (Lord Mackay of Clashfern, Lord Chancellor, Lord Goff of Chieveley, Lord Jauncey of Tullichettle, Lord Mustill, Lord Hoffmann) 14 November 1996

The activities of an independent contractor at an employer's site could form part of the conduct of the employer's undertaking, so as to render the employer liable to prosecution under the Health and Safety at Work Act 1974 for an injury to one of the contractor's employees.

The House of Lords dismissed an appeal by Associated Octel Co Ltd, and affirmed the decision of the Court of Appeal ([1995] ICR 281) dismissing Octel's appeal against conviction, at Chester Crown Court on 19 March 1993, for an offence under section 33(1)(a) of the 1974 Act.

By section 33(1)(a) it is an offence for an employer not to discharge his duty, under section 3(1),

to conduct his undertaking in such a way as to ensure, so far as is reasonably practicable, that persons not in his employment who may be affected thereby are not thereby exposed to risks to their health or safety.

Octel operated a large chemical plant at Ellesmere Port. In June 1990, while the plant was shut down for annual maintenance, a firm called Resin Glass Products Ltd (RGP) was engaged in repairing the lining of a tank. One of RGP's employees, Mr Cuthbert, was cleaning the lining of the tank with acetone, a supply of which he had in an old paint bucket. The electric bulb by whose light he was working broke and ignited the flammable vapour from the acetone in the bucket, causing a flash fire in which Mr Cuthbert was badly burned.

Like other contractors at Octel's plant, RGP's employees operated under a "permit to work" system. For every job they had to fill in a form saying what they were going to do and obtain authorisation from Octel's engineers, who would consider what safety precautions were needed.

To rebut the defence that prevention of the accident had not been "reasonably practicable", the Crown adduced evidence showing that the permit-to-work system had been operated in a perfunctory manner. Octel had supplied Mr Cuthbert with protective clothing and a face mask, but not a special air lamp or a closed container for the acetone or forced air extraction for the tank.

Octel submitted it had no case to answer because the injury to Mr Cuthbert was not caused by the way in which Octel, as opposed to RGP, had conducted its undertaking. Control was essential to liability under section 3(1) and Octel had no right to control the way its independent contractors did their work.

Raymond Walker QC and Julian Waters (Hill Dickinson Davis Campbell, Liverpool) for Octel; Hugh Carlisle QC and Ian Burnett (Treasury Solicitor) for the Crown.

Lord Hoffmann said Octel's argument was based on a confusion between two quite different concepts: an employer's vicarious liability for the tortious acts of another, and a duty imposed upon the employer himself.

Section 3 was not concerned with vicarious liability. It imposed a duty on the employer himself. That duty was defined by reference to a certain kind of activity, namely the conduct of his undertaking. Section 3 required him to do it in such a way as did not create risks to people's health and safety. If he engaged an independent contractor to do work which formed part of the conduct of his undertaking, he must stipulate for whatever conditions were needed to avoid those risks and were reasonably practicable. That was why Octel insisted its contractors adhered to the permit-to-work system.

The question was simply whether the activity in question could be described as part of the employer's undertaking. In most cases the answer would be obvious. Octel's undertaking was running a chemical plant. It was part of the conduct of that undertaking to have the chlorine tank repaired.

Whether the activity which had caused the risk amounted to part of the conduct by the employer of his undertaking must in each case be a question of fact. As such it should be left to the jury. It was not done so in this case. But, since on the undisputed facts a properly instructed jury could only have concluded that having the tank repaired was part of the conduct of Octel's undertaking, the conviction should be affirmed.

Paul Magrath, Barrister