PurposeTo investigate the effect of watching 3-dimensional (3D) television (TV) on refractive error in children.MethodsSixty healthy volunteers, aged 6 to 12 years, without any ocular abnormalities other than refractive error were recruited for this study. They watched 3D TV for 50 minutes at a viewing distance of 2.8 meters. The image disparity of the 3D contents was from -1 to 1 degree. Refractive errors were measured both before and immediately after watching TV and were rechecked after a 10-minute rest period. The refractive errors before and after watching TV were compared. The amount of refractive change was also compared between myopes and controls. The refractive error of the participants who showed a myopic shift immediately after watching TV were compared across each time point to assure that the myopic shift persisted after a 10-minute rest.ResultsThe mean age of the participants was 9.23 ± 1.75 years. The baseline manifest refractive error was -1.70 ± 1.79 (-5.50 to +1.25) diopters. The refractive errors immediately after watching and after a 10-minute rest were -1.75 ± 1.85 and -1.69 ± 1.80 diopters, respectively, which were not different from the baseline values. Myopic participants (34 participants), whose spherical equivalent was worse than -0.75 diopters, also did not show any significant refractive change after watching 3D TV. A myopic shift was observed in 31 participants with a mean score of 0.29 ± 0.23 diopters, which resolved after a 10-minute rest.ConclusionsWatching properly made 3D content on a 3D TV for 50 minutes with a 10-minute intermission at more than 2.8 meters of viewing distance did not affect the refractive error of children.

In this study, fire case analysis and fire type and risk analysis were conducted for each process according to the ISO 17776 checklist to determine the firefighting activities and worker evacuation areas in case of a fire in a petrochemical plant. Therefore, fire modeling was performed for storage tanks with the largest fire load according to the wind speed and combustibles in order to analyze the radiant heat and smoke behavior. The effects of radiant heat and smoke were increasingly high in the order of n-heptane, gasoline, and diesel. Moreover, the firefighting activities and worker evacuation areas varied greatly depending on the wind speed rather than combustibles. However, because the results of the study cannot exclude the possible dependence on the fire modeling, it is necessary to generalize and standardize the results of the study by accumulating data through various scenarios.

Plant facilities should exhibit the same fire resistance performance as general buildings even though they generally have combustibles with high fire risk, unlike general buildings. Therefore, in this study, the fire resistance performance was evaluated considering the cellulosic fire presented in KS F 2257-1, which is the standard for evaluating fire resistance performance of general buildings, and hydrocarbon fire that can occur in the plant presented in UL-1709.