What hazard class is indicated by a placard with a white diamond, skull and crossbones at the top, and the number 2 at the bottom?

The placard described features a white diamond with a skull and crossbones symbol at the top and the number 2 at the bottom, which is indicative of poisonous gases. The skull and crossbones symbol universally represents toxic materials that can cause severe health risks upon exposure, especially by inhalation. The number 2 signifies the degree of toxicity and relates to the specific classification within the hazard communication standards.

Poisonous gases pose serious threats to human health, making it critical for first responders and firefighters to recognize and understand this hazardous material. Understanding the signs and symbols associated with hazardous materials is essential for ensuring safety and properly managing emergency situations involving toxic substances.

The other classifications, such as flammable gases, corrosive materials, and radioactive materials, are represented by different symbols and color codes, making them distinct from what is indicated on the placard in question.