This paper presents the results of a research carried out in the states of Pernambuco and Rio Grande do Sul, Brazil about differences and similarities in the graphic representation of safety signs at factories of food, steel, shoes and construction/ building industries, together with their workers' opinions on the security signs. The overall results show differences in the sign structure across the states, confirming the influence of cultural differences on the design of safety signs, which must be taken into account during the design process.