Methodology for the evaluation of potential optical radiation hazards .has been developed in response to the increasing use of high radiance optical sources, such as lasers, compact arc lamps, tungsten-halogen lamps, and electronic flash lamps. Recent biological investigations of injury from ultraviolet radiation and studies of chorioretinal injury from high radiance sources permit a realistic ocular hazard evaluation. Safe exposure criteria that may be readily applied to practical situations have been developed from the available biological data and from experience with occupational hazards. Hazard evaluation techniques, hazard data, and general control measures are provided for a number of commonly encountered ultraviolet, visible, and infrared sources.

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This study presents a Web-based interactive homework quiz and tutorial package that we have devised to improve the learning of first-year undergraduate chemistry students. We developed this automated scheme, based on WWWAssign, to produce randomly generated quizzes from a large database of questions, instantaneously grade that homework, give a fully-worked solution, and provide individually targeted tutorial assistance. Success in these quizzes was a necessary requirement before taking supervised tests. We found a positive correlation at the p= 0.1 level (90%) between voluntary extra use of the quizzes in the interactive package and the final course grade. All students undertook more quizzes than the base course requirement even though the quiz grades did not contribute to the total course grades. We suggest that students were motivated to pursue additional practice with the quizzes and associated tutorial information, as they perceived some benefit in this student-centered study tool and could access it at any time.