According to OSHA, what are the soil types classified for excavation safety?

The classification of soil types for excavation safety according to OSHA is based on a specific system that categorizes soil into four distinct classes: A, B, C, and D. Type A soil indicates the most stable soil with the greatest resistance to excavation collapses, while Type B soil is less stable but still relatively safe for excavation with proper precautions. Type C soil is considered to be the most hazardous, with a high susceptibility to collapses, and requires additional safety measures.

This classification system is vital for ensuring the safety of workers during excavation activities, as it helps determine the necessary protective measures based on the inherent stability of the soil. By understanding these classifications, contractors can implement appropriate shoring or sloping techniques to minimize the risk of cave-ins, thus promoting a safer work environment.

The other alternatives do not correctly represent the OSHA classification system. Types I and III or the numerical options like 1, 2, and 3 do not align with OSHA’s recognized categories. Therefore, the classification of soil types A, B, C, and D is the standard used for excavation safety according to OSHA's regulations.