Seaports play a very important role in the international commerce. They have influence on very large geographical areas and carry out very complex operations with large volumes of goods. Maintaining high efficiency in the transportation of goods as well as a low level of risk within the port area is very important. In order to reduce this risk, it is necessary to analyze the different components of the risk assessment: frequency and consequences. These two parameters are influenced by numerous and imprecise factors. In the present work, an analysis of the principal uncertainty sources present in the calculation of the frequency rate for a maritime accident is presented. Taking into consideration the variables that can influence the frequency and a standard value of this parameter, a modification is made in order to get better assessment of the frequency of accidents in ports. The developed method is based on a fuzzy modifier which reduces the uncertainty in the seaports accident frequency,