Selection of risk factor identification methods
Thread Content
I work at a chemical plant, where I am required to identify hazards throughout the entire production system every year. The LEC method is being used; I wonder how other colleagues approach this aspect? In my work, I’ve found that using the LEC method for identification is not only troublesome but also not very practical; I wonder if my colleagues share the same opinion. Identification is not only a requirement of the occupational health and safety management system but also of safety standardization; therefore, a great deal of work must be done each year, and it is interesting to see how peers handle this.
A simple and practical semi-quantitative method for assessing the risk associated with people working in potentially hazardous environments. It evaluates the level of risk of casualties among system personnel by using the product of the indicator values of three factors related to the system’s risk rate; these three factors are: L – the likelihood of an accident occurring ； E – The frequency of human exposure to this hazardous environment ； C—The loss consequences that can occur in the event of an accident. However, obtaining scientifically accurate data on these three factors is a rather complicated process. To simplify the evaluation process, a semi-quantitative scoring method can be adopted: different scores are assigned to the various levels of the three factors, and the risk level is then determined by the product D of these three scores. That is: D=LEC
In fact, I think this method is quite practical as long as it is used properly. At present, our risk assessment form does not include an E factor; risk is calculated as probability (frequency) * severity. The probability is divided into four levels based on the company’s actual conditions (of course, it can also be divided into more or fewer levels), with higher levels indicating a greater probability. Severity is divided into five levels, with higher levels meaning greater risk. A risk assessment form should be created, and threshold values should be set – for example, values above 16 are considered high risks that require immediate corrective action； Those greater than 9 represent a medium risk and should be resolved as soon as possible ； If it is less than 9, execution can be postponed
In fact, although risk assessment is important, what is most crucial is to take action to address the identified risks until they are completely resolved. Otherwise, it becomes mere theory – having well-written articles does not actually provide any real benefit to those who are at risk.
What was said on the 4th floor makes a lot of sense; the focus of risk assessment lies in the details, and the key is to put it into practice. Our company also uses the LEC method.
Safety first; don’t treat it as a mere formality
The LEC method is a simple and easy-to-use approach, but it inevitably involves too many human factors during use, and the analysis results are closely related to the skill level of the analyst. The risk level assessed by the LEC method (which can be considered merely a concept rather than something concrete) also makes it difficult to develop targeted countermeasures against that risk. It is recommended to use the HAZOP analysis method, although it is more complicated to apply. HAZOP study is an effective method for identifying design flaws, analyzing the impact of equipment failures and misoperations on the process, and exploring countermeasures. It is a process of analyzing the causes and consequences of potential process abnormalities that may occur in each pipeline and on each device shown in the PID diagram, as well as determining the appropriate countermeasures to take, all in order to ensure safety. The characteristics of HAZOP studies are: (1) focusing on each pipeline and each piece of equipment that makes up the process, as a straightforward analytical method ； (2) Use keyword sequencing to identify potential process abnormalities and prevent omissions ； (3) Leverage the company’s technical and resource advantages by bringing together experts and professionals from various fields to conduct joint discussions ； (4) Record the analysis results in a standardized and unique table format ； (5) The general steps for carrying out a HAZOP study include: preparing design documents, formulating an implementation plan, compiling a pipeline list, introducing the objectives and methods of the HAZOP study for this project, holding review meetings, documenting the results of the reviews, preparing a table of countermeasures, conducting studies by the design team and implementing the corresponding measures, obtaining confirmation from the owner, and finalizing the report.