Quantitative Risk Analysis (ORA) Q1: What is the calculated probability of a fire in a year, with the probability and frequency data as given in Fig. 1? (Examine the logic tree). In this plant welding happens on average 4 times per year for 3 hours each time. Also, electric motors drive in the plant on average twice per day for 25 minutes each time. Figure 1 Q2: What is the value of Bow-tie diagram that makes it often required by the regulators? Hazards and Operability Studies (HAZOP) Q3: Refer to the reactor system shown in Fig. 2. The reaction is exothermic. A cooling system is provided to remove the excess energy of reaction. In the event of cooling function is lost, the temperature of reactor would increase. This would lead to an increase in reaction rate leading to additional energy release. The result could be a runaway reaction with pressures exceeding the bursting pressure of the reactor. The temperature within the reactor is measured and issued to control the cooling water flow rate by a valve. Perform HAZOP Study for the parameter cooling water flow (fill in the blank in Table 1.) Figure 2 Table 1 Q4: Name two Pros and two Cons for the HAZOP Method