In pp plastic sdn. bhd, propylene oxide with molecular weight of 58.08 (tlv-twa: 2 ppm) is being splash filled into a 300 liters storage tank with the constant filling rate of 0.001 s-1. the filling is done through a manway of 12 cm diameters. the local ventilation rate is 0.5 m3/s. estimate the concentration of the propylene oxide and the percentage of fatalities if all workers in pp plastic sdn. bhd. are exposed to propylene oxide with vapour pressure of 538 mmhg for 1 hour.