Being able to evaluate risks is an important task in many areas of human activity: economics, ecology, etc. Usually, environmental risk assessment is carried out on the basis of multiple and sometimes conflicting factors. Using multiple criteria decision-making (MCDM) methodology is one of the possible ways to solve the problem. Analytic hierarchy process (AHP) is one of the most commonly used MCDM methods, which combines subjective and personal preferences in the risk assessment process. However, the AHP involves human subjectivity, which introduces vagueness type of uncertainty and requires the use of decision making under those uncertainties. In this paper, work with uncertainty is considered using fuzzy-based techniques. The paper also analyses the ecological risk assessment towards human health in case of gaseous substance escape at a chemical factory using the fuzzy analytical hierarchy process.