Can HAZOP360 be used to perform a CHAZOP?
Yes! HAZOP360 allows users to make their own custom nodes and deviations which can accommodate traditional HAZOPs, as well as CHAZOPs.
What is a CHAZOP?
A Control Hazard and Operability Study (CHAZOP) is a procedure for carrying out the safety and reliability analysis of existing or planned control and computer systems.
In the early 1980's, the trend of replacing manual operations with more advanced automated operations began, and continues to this very day. Localized control panels were moved to centralized control rooms, and the industry saw the evolution and sophistication of programmable electronic systems, including
Distributed Control Systems (DCS)
Hardwired relay systems replaced by programmable logic controllers (PLCs)
Supervisory Control and Data Acquisition (SCADA) systems
This trend has given rise to greater operability, flexibility and capability within facilities, but it is also accompanied by increased complexity and more components that have a certain probability of malfunctioning or failing. Ultimately, in the 2000's, the components of a Control System became potential hazards that needed to be included as part of the process hazard analysis. This is where the CHAZOP was born.
Similar to HAZOPs, CHAZOPs use a framework of guidewords to analyze potential causes that lead to hazardous consequences. Some examples of CHAZOP guidewords are as follows:
Loss: evaluates the impact to the design when a function is lost, including power supply, processor capability, memory, communications channels from/to I/O signals, etc.
Range: evaluates the impact to the design if a signal is either being distorted or is out of range
Mixture: evaluates the impact to the design when there is a failure pattern of inappropriate combinations of I/O channels in relation to the hardware organization of the system
Version: evaluates potential consequences of either changes to the hardware platform or upgrades to the system software on the integrity of the application software
Security: evaluates the potential consequences of unauthorized access to the system
HAZOP360 allows users to use their own guidewords to develop custom deviations and build a PHA file that best suits their needs.
