A hospital knows the cost of installing energy-saving timer switches to a lighting system. The NPV is positive. However, the firms accountant has been shown the calculation. She notes that (a) no account has been taken of the fact that the use of timer switches will increase insurance costs due to added risk and (b) that no account has been taken of the internal management costs of the project though there is currently spare capacity in the management team to effect the change. Discuss whether either (a) or (b) or both might change the basis of the calculations.