The 1949 case revolved around whether it was "reasonably practicable" to prevent even the smallest possibility of a rock fall in a coal mine.
[1] Mr Edwards died in an accident after the supporting structure for the mine roadway gave way.
Asquith stated in his judgement: Reasonably practicable is a narrower term than ‘physically possible’ and implies that a computation must be made... in which the quantum of risk is placed in one scale and the sacrifice involved in the measures necessary for averting the risk (whether in time, trouble or money) is placed in the other and that, if it be shown that there is a great disproportion between them – the risk being insignificant in relation to the sacrifice – the person upon whom the obligation is imposed discharges the onus which is upon him.This case established the concept of "reasonable practicability."
The Court of Appeal decided that "reasonably practicable" was a more narrowly defined phrase than what was "physically possible."
[2] In addition, the court in Edwards determined that the size and wealth of the company should have no bearing on such decisions.