chemical risk assessment in a chemical laboratory based on three different techniques

background: the use of chemicals is essential in education resulting in exposure to these pollutant in a variety of chemical and research laboratories. chemical contaminants in chemical laboratories are in different forms and chemical exposure risk assessment is important for choosing appropriate controls in protecting the health of operators, experts and students. for risk assessment in chemical exposures, several techniques were introduced that their use should be assessed. this research was done with the aim to introduce the most appropriate technique in chemical risk assessment by using three chemical risk assessment techniques. materials and methods: this was a descriptive research done in one chemical laboratory. this research had been defined in several stages: in the first phase, the list of solid and liquid chemicals were prepared and full physicochemical properties of substances as well as toxicity and health risk of them were collected. finally chemical risk management self-assessment model (chem-sam), university of wollingong (uow) risk assessment and semi-quantitative risk assessment method (sqra) methods were used and compared. results: there was significant difference between sqra methods and uow technique while no significant difference was observed between sqra methods and chem-sam model. conclusions: all three techniques are simple, but the results were similar in sqra methods and chem-sam model, so these two methods can be replaced in chemical risk assessment. in order to control the identified risks, this research has recommended programs, control measures, improving local exhaust ventilation systems, personal protective equipment and training of personnel.