Quantitative risk assessment techniques are changing the way in which amusement rides are designed, inspected and operated. Modern rides are becoming dependent on computer-based technology with control systems allowing rides to perform increasingly complex functions at very high speeds. Passenger safety can depend on the correct operation of control systems and their failure could compromise safety.
Such developments mean that quantitative risk assessments are increasingly being applied to amusement rides.1 A quantitative risk assessment involves calculating the magnitude of a potential loss and the probability that such loss will occur. An acceptable risk is only understood or tolerated where the cost or difficulty of implementing an effective countermeasure exceeds the expectation of loss.