Suppose that in your facility, you have two tanks that are connected with a pipe or a piping system, where hazardous chemicals in one tank are transferred to the other tank through the pipe or the piping system. The continual process of monitoring the liquid level in each tank, increasing or decreasing it as needed, and transporting the chemicals from the source tank to the target tank is a potentially hazardous process that involves risk. During this process, for example, if the level control malfunctions, the pressure in the pipe or the source tank could increase too rapidly and cause the chemicals in the source tank to leak out, causing damage to the environment or personnel.
After you identify the hazardous scenarios associated with a process, you can use Hazards Analysis to:
- Define the characteristics of the scenarios, including the risks that they include.
- Assess the likelihood of the risks in each scenario actually occurring.
- Identify ways to prevent the risk in each scenario from occurring.
- Make recommendations for actions that can be taken within the facility to prevent the risks in each scenario from occurring or to mitigate the risks in some way (e.g., lower the severity of the safety or environmental impact).
Suppose that, for the preceding process (transporting hazardous chemicals between two tanks), you identify a risk that the pressure monitor will stop working and a chemical spill will occur. Through a risk assessment, you also determine that the chemical spill is very likely to cause a negative impact to both human safety and the environment. Based on this assessment, you might determine that the only way to prevent the risk is to be alerted when the pressure in the tank is increasing too quickly. In this case, you may recommend that a high pressure alarm be put in place to alert someone if the pressure in the tank is rising too quickly. You may recommend to test the alarm on a periodic basis to ensure the availability of the alarm.