Marine oil pollution is a major environmental challenge that threatens marine ecosystems, coastal economies, and human health. As Iran's only ocean port, handling a high volume of ocean-going vessel traffic, Chabahar Port faces a significant risk of oil-related incidents. Despite existing research on the detection and cleanup of oil pollution, the literature lacks a study that comprehensively identifies the factors influencing the improvement of response operations and establishes a causal hierarchy among them. This study was conducted to identify and hierarchically classify these factors at Chabahar Port.

This study is applied in terms of objective, descriptive-survey in terms of data collection, and quantitative in nature. The statistical population consisted of personnel from the Maritime Affairs Division of the Sistan and Baluchestan Ports and Maritime Administration, shipping companies, and the Department of Environment (N=35); 30 individuals participated via purposive non-random sampling. Through a systematic review of domestic and international literature, 22 influential factors were identified. Questionnaire reliability was assessed using Cronbach’s alpha coefficient based on a pilot sample of 10 participants. Content validity was evaluated via the Delphi method over two rounds involving 20 experts (Kendall’s coefficient = 0.92; Sig < 0.05). Finally, the factors were categorized using Interpretive Structural Modeling (ISM) and MICMAC analysis.

All 22 factors were validated through the Delphi process. The ISM results classified the factors into three causal levels; the third-level factors—comprising the identification of pollution sources, infrastructure development, and international standards—exhibited the highest driving power and the lowest dependence, identifying them as the system's primary drivers. Based on the MICMAC analysis, the factors were categorized into four groups: independent, dependent, linkage, and autonomous.

The results indicated that one factor fell into the independent group, three into the dependent group, and eighteen into the linkage group. It can be concluded that by identifying and prioritizing these influential factors, financial, human, and technical resources for combating marine oil pollution can be allocated more effectively, thereby preventing resource wastage or allocation errors. This prioritization of resources can serve as a basis for strategic planning by managers in this field.