He brought a bottle of water and put it in thinner to use for mixing paints on his work. Before leaving work, he put the drinking water bottles that he brought up to eat as well as the clear thinner bottles into garbage bags so that he could take them down and throw them away. But the weather was very hot while walking downstairs carrying garbage bags. Therefore, the employee saw water left in the garbage bag. So he washed his face to cool down, but the bottle that was picked up to wash his face was a thinner bottle that employees used at the work