The famous snail in the ginger beer case, Donoghue v Stevenson, is, you might say, the godfather of the tort duty of care in negligence. In that case the duty was not to cause personal injury but the duty was later expanded to include physical damage to other property. A key issue in Donoghue was the fact that the danger was hidden, but what if a dangerous defect is discovered before causing damage. Is there still liability in tort?
An aerospace component factory had safety devices installed to protect against the fire risk in a number of heated tanks. One of the safety devices failed and twice caused a fire which was swiftly put out. The manufacturer bought an alternative safety device but, some days later, before it was installed, the original safety device failed again and the resulting fire caused 20 million worth of damage. Was the manufacturer of the faulty original device still liable?
No, said the Court of Appeal. The collective knowledge of the relevant employees, those to whom the directors of the component company had entrusted the safe maintenance and operation of the tanks, should be attributed to the company. And once the end user is alerted to the dangerous condition of a chattel, if they voluntarily continue to use it and personal injury or damage is caused as a result, they normally do so entirely at their own risk.