Abstract Background: Acrylonitrile butadiene styrene granules heat up from169 to 32 0 C in the production of household appliance, which results in the decomposition of white smoke in the work place. Objective: Staff respiratory exposure with ABS granules vapors and dust examined. Methods: This analytical case-control study was performed on 78 persons of appliance manufacturing company in Qazvin, in 2016. Particles measurement 0.3 and 2.5 microns by Micro Dust Pro devices and Dust Counter and

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... irometry test were performed by Minispir. FEV1, FVC, FEV1/FVC parameters before and after invention platform on 8 meters height and respiratory signs staff complaints were considered by COPD assessment test. Findings: Forty-eight persons that exposed with vapor and dust ABS plastic material mostly had a lot of complaints to the frequent respiratory symptoms of cough and sputum occasionally. Spirometry indices coldwall staffs on the second floor including FEV1, FVC and the ratio FEV1/FVC were significantly decreased respectively (6.52%, 5.66%, 3.56 lit) during 2 years (P<0.05) and for coldwall staffs on the first floor, FEV1 and FVC significantly decreased respectively (9.26% and 5.6%) (P<0.05). But the ratio FEV1/FVC was not significant decreased. The three above mentioned indices for injection plastic staffs had significantly reduced (P<0.05), and increased for administrative staffs. Concentration of inhaled particles was 0.23±0.067 on the floor and particle at platform 0.62±0.24 mg/m 3. Conclusion: It must be avoided to create a platform on the top of the hot source, such as plastic injection process.