ABSTRACT
<p><b>OBJECTIVE</b>Risk assessment and risk control for occupational exposure to chemical toxicants were performed on an isophorone nitrile device with an annual production of 5,000 tons, based on improved Singaporean semi-quantitative risk assessment method, with consideration of actual situation in China and in the present project.</p><p><b>METHODS</b>With the use of engineering analysis and identification of occupational hazards in the improved Singaporean semi-quantitative risk assessment method, hazard rating (HR) and risk assessment were performed on chemical toxicants from an isophorone nitrile device with an annual production of 5,000 tons.</p><p><b>RESULTS</b>The chemical toxicants in the isophorone nitrile device were mainly isophorone, hydrocyanic acid, methanol, phosphoric acid, sodium hydroxide, and sodium cyanide; the HR values were mild hazard (2), extreme hazard (5), mild hazard (2), mild hazard (2), moderate hazard (3), and extreme hazard (5), respectively, and the corresponding exposure rating (ER) values were 2.09, 2.72, 2.76, 1.68, 2.0, and 1.59, respectively. The risk of chemical toxicants in this project was assessed according to the formula Risk = [HR×ER](1/2). Hydrocyanic acid was determined as high risk, sodium hydroxide and sodium cyanide as medium risk, and isophorone, methanol, and phosphoric acid as low risk. Priority in handling of risks was determined by risk rating. The table of risk control measure was established for pre-assessment of occupational hazards.</p><p><b>CONCLUSION</b>With risk assessment in this study, we concluded that the isophorone nitrile device with 5,000 ton annual production was a high-occupational hazard device. This device is a project of extreme occupational hazard. The improved Singaporean semi-quantitative risk assessment method is a scientific and applicable method, and is especially suitable for pre-evaluation of on-site project with no analogy.</p>
Subject(s)
Humans , Cyclohexanones , Nitriles , Occupational Exposure , Risk AssessmentABSTRACT
Objective The purpose is to report the clinical result of repairing defection in hand surgery by using both the vascular tissue flap and external fixators. Methods The vascular tissue flap including bone flap and joint flap to repair the complex defection (soft tissue, bones and joints) in hand and forearm were applied in 9 cases. At the same time in surgery,injured bones and joints were fixed by A-O and mini external fixators in order to keep the non-injured joint actively and accelerate the cure of bones. Result All 9 cases were applied successfully with the all transplanted tissue survived. Pulling about the external fixator about 10- 12 weeks after surgery showed bone union and the f unction of hand recovered satisfactorily' Conclusion it is a reliable method for repairing the complex tissue defection in hand and forearm by combining external fixation of traumarology and microsugery technique. And it is also characterized by a minor injury in transplanted bones,early exercise for joints,flap circulation observed conveniently,and nursing easily.