In: Civil Engineering
4. A number of methodologies and techniques for risk assessment exist that range from simple to complex. Describe the six methodologies/techniques summarized in NFPA 1600.
Answer-
Methodologies and techniques for risk assessment given in NFPA 1600 that ranges from simple to complex are described as under:
1) “What-if”: This methodology helps in identifying the type of hazard which can result in dangerous situations. This methodology is more dependent upon the individuals with proper knowledge about the area of operations, more importantly this methodology is dependent upon the correct questioning by the knowledgeable individuals in regards to the hazards and hazardous situations.
2) Checklist: As the name suggests a checklist is a list of items which help in identifying both situations created by hazard and type of hazard. This list helps in comparing the hazards with standards. This technique also relies upon the quality or accuracy of the checklist and also the awareness and experience of the user using it.
3) What-if/checklist: Above two mentioned method in combination forms this method or technique, this risk assessment method uses both the techniques, thus the questions are asked using the what-if method and are accompanied by the checklist items, same as above two methods this method also relies upon exhaustive nature like asking correct questions and experience of the user regarding the hazards.
4) Hazard and operability study (HAZOP): This technique is one of the most important technique in risk assessment, this method just not only require knowledgeable individuals but also require a set of individual that form the interdisciplinary team, In combination this technique consume more time but it is effective until the whole team function as one team. This technique requires thorough experience regarding the hazards.
5) Failure mode and effects analysis (FMEA): This technique examines elements involves in the process individually, this helps in determining the effect of the element when one or more of them gets failed. This technique helps in predicting the failure in the system, same as like HAZOP technique, this method requires an experienced team which can help in predicting the failure like equipment failures, this technique depends upon the team credential and scope of the entire system that needs to be checked, this method applies bottom down approach.
6) Fault-tree analysis (FTA): The identification of the event with this technique is done with the help of top down approach, also this identifies the causes from the range and also helps in presuming the undesirable events, this technique requires competence in FTA process and is depend upon the given process, this process also requires knowledgeable team and their credentials also the depth and experience of the hazards plays an important role in accuracy of this technique.