triangular shape,
black letters on a yellow background with black edging (the yellow part to take up at least 50 % of the area of the sign).
Directive 1999/92/EC of the European Parliament and of the CouncilShow full title
Directive 1999/92/EC of the European Parliament and of the Council of 16 December 1999 on minimum requirements for improving the safety and health protection of workers potentially at risk from explosive atmospheres (15th individual Directive within the meaning of Article 16(1) of Directive 89/391/EEC)