• In the case of Howmet Ltd v Economy Devices Ltd [2016] E.W.C.A. Civ 847, it was held that where the end user voluntarily continues to use a defective chattel after being informed about its dangerous condition, they do so at their own risk. The manufacturer of the device in these cases will not be held liable for the consequences of its use.

Facts of the Case

  • C manufactured precise components for the aerospace industry. In 2005, C decided to replace the ‘Grain Etch Line’ (GEL) at their factory. A GEL is a series of tanks metal castings are dipped in to expose the grain.
  • C engaged a company to design, supply and install the GEL. They installed a GEL with 8 separate tanks.
  • The tanks were coated with inflammable polypropylene. The installation company had them fitted with thermolevels to monitor the liquid levels in the tanks and automatically turn the heater off at dangerous levels.
  • In 2006, the installation company purchased thermolevels from D. The thermolevels were installed after several design changes were made by the installation company, including an ‘extension plug and socket.’
  • On 12th December 2006, a small fire occurred in one tank due to a failing sensor in the thermolevel. This occurred because the extension ‘plug and socket’ had corroded. This was re-soldered and covered with a heat shrink sleeve.
  • Similar issues occurred on the 11th January and the 29th January 2007. This brought the issues of the defective thermolevels to the attention of at least 6 employees. Alternative devices were brought in without replacing the thermolevels.
  • In the early morning of 12th February 2007, an employee mistakenly turned on the heater of the empty tank 6. The sensor failed to operate, and the polypropylene caught fire. With no one around to catch the blaze, the fire engulfed the factory.


  • Did D owe a continuing duty of care to C notwithstanding C had knowingly continued to use the defective thermolevels?

Held by the Court of Appeal (Civil Division)

  • Finding for D, that 6 employees had knowledge that the thermolevels were defective, and this knowledge should be attributed to C.
  • Once the thermolevels passed through the factory gate, D had no control over who or how it was used. C could not rely on the ignorance of its senior management because employees had failed to report the danger.
  • Since C continued to use the thermolevel after becoming aware of its dangerous condition, C did so at his own risk.
  • Ultimately, the fire was caused by the failure of a system C put in place to protect the tank after becoming aware of the thermolevel’s defects. This situation defeated C’s claim in negligence whether D’s duty of care had ended, or by failing to establish causation.

Lord Justice Jackson

  • Once an article has passed through the factory gate, the original manufacturer has no control over it. The law therefore imposes restrictions upon a manufacturer’s liability to the user.
  • D & F Estates v Church Commissioners for England [1989] 1 AC 177 outlined that if the product’s defect causes personal injury or property damage beyond the product itself, then D would be liable. However, if the defect is discovered before such damage is caused, the product is now defective, but no longer dangerous.
  • If one person in the corporate hierarchy becomes aware of a dangerous situation in the workplace and fails to report up the line (in breach of duty), the company cannot rely upon the ignorance of its more senior managers in resulting cases.

“In my view by early February 2007 C knew (alternatively must be taken to have known) that the thermolevel was malfunctioning. C continued to use the GEL without installing any alternative safety mechanism to switch off the heater when the water level fell. They simply relied upon operator vigilance during the week and a special arrangement for tank 6 at the weekends. The effective cause of the fire on the 12th of February 2007 was the failure of the system which C had put in place to protect tank 6 following the malfunction of the thermolevel” [95].