Howmet Ltd v Economy Devices Ltd & Ors

A manufacturer of a safety device owes a duty to take reasonable care where the device is supplied for use in a foreseeable safety-critical application. That duty is not discharged merely because the user could have made further enquiries or noticed the absence of a CE mark. A claimant must nevertheless prove that the defendant’s breach caused the loss and that it was relying on the product as a safety device when the loss occurred. Conduct breaks the chain of causation only where it is sufficiently unreasonable, ordinarily reckless, to make the claimant’s conduct the true cause of the loss.

Howmet claimed damages exceeding £20 million from Economy Devices Ltd (“EDL”) after a fire at its factory. The fire followed the failure of an EDL thermolevel to prevent heaters in a hot-water tank from operating when the tank was empty. Howmet alleged negligent design, manufacture and instructions, and breach of statutory duty under the Electrical Equipment (Safety) Regulations 1994.

The court found that the thermolevel was unreliable, unsuitable as a safety device and inadequately documented. The negligence claim failed because Howmet could not prove the precise mechanism causing the failure, particularly the alleged incorrect setting of the sensitivity control. The statutory claim also failed because Howmet had not proved that it was relying on the thermolevel as a reliable safety device immediately before the fire.

1. The claim was dismissed. The court found that the thermolevels were unreliable and unpredictable, difficult to set, and unsuitable for safety-critical use. EDL had failed to implement a proper testing regime and had supplied manifestly unsatisfactory operating instructions.

2. The use of the thermolevel in the grain etch line was within the contemplation of its manufacturer. The relevant configuration complied with the applicable Code of Practice, and a built-in over-temperature device was not mandatory. That did not make the thermolevel safe or relieve EDL of its duty.

3. The principle in Donoghue v Stevenson [1932] AC 562 was not confined to products causing direct physical damage. It could apply where a defective safety component failed to prevent another component from causing property damage.

4. The absence of a CE mark did not discharge EDL’s duty. A purchaser was entitled, in the absence of contrary knowledge, to assume that a product placed on the market by a reputable manufacturer had been properly designed and was fit for its apparent purpose.

5. The fire resulted from the thermolevel failing to cut off the heater, but the court could not identify the probable mechanism. Incorrect adjustment of the potentiometer was possible and would have implicated EDL’s defective design and instructions, but it was not proved on the balance of probabilities. Applying Nulty v Milton Keynes Borough Council [2013] BLR 134, the court could not select the least unlikely of several causes and treat it as probable.

6. For the statutory claim, the thermolevel was unsafe within the meaning of the Consumer Protection Act 1987 and the 1994 Regulations. Nevertheless, Howmet failed to prove that it relied on the thermolevel as a reliable low-level cut-out after the later January incident. The statutory claim therefore failed.

7. Howmet’s conduct after the December incident was not sufficiently unreasonable to break the chain of causation. The court could not determine whether its conduct between 2 and 12 February 2007 had broken the chain. Since causation and reliance were not proved, the issue did not affect the result.

8. Contributory negligence was addressed provisionally. Howmet was seriously at fault in procuring and operating the system, while EDL had marketed a defective safety device. If liability had arisen, it would have been apportioned 75 per cent to Howmet and 25 per cent to EDL.