Qualitative Evaluation of Laboratory hoods in Campus Laboratory and Food and Drug Administration of Qazvin University of Medical Sciences and taking intervential action

Background and Objective: various type of chemical and biological agent with different health effect are used in laboratorial environment. Some researches indicated the risk of respiratory exposure in university laboratories. Present study aims to evaluate the operation of laboratorial hoods in campus and food and drug organization in Qazvin University of medical science. Materials and Methods: In this study, 19 chemical and 10 biological hoods in campus and food and drug organization were evaluated according to ACGIH standards. Different factors like Face velocity and structural feature and their accordance to standards were examined and resulted data were analyzed in SPSS software, version 21. In hoods with low face velocity،ventilation system was designed using velocity pressure method. Results: According to the results, 92.6 present of hood had inappropriate condition and maximum face velocity was 158 fpm.67persent of chemical hoods had obvious leakage and they were improperly connected to roof channels by flexible duct. The result of velocity assessment in hoods connected to central ventilation system indicated 60% increase in airflow and 10 ± 92 fpm supply velocity.in order to use air diluting capacities ،ventilation chimney was installed at the top of building to prevent contaminated air return into building Conclusion: Most hoods did not perform well and were unable to control respiratory exposure. Mainly hoods have their own ventilator which doesn’t have the ability to overcome the pressure drop in the discharge paths and meanwhile make a lot of noise.