Which soil category is classified by OSHA as stable?

The correct identification of Class B soil as stable by OSHA is significant for various reasons in the context of excavation and construction safety. Class B soils are characterized as cohesive soils, which generally have good strength and stability. These soils can include materials such as clay and silt that possess higher cohesion than granular soils, making them less likely to collapse or yield under stress compared to less stable soil types.

Understanding this classification is crucial for safety measures during excavation. Class B soils require specific protective measures to ensure the safety of workers. These might include sloping, shoring, or using trench boxes to prevent soil collapse, which can be a severe hazard in any excavation work.

In contrast, other soil categories such as Class C, classified as loose, granular, and relatively weak, do not provide the same level of stability and require more stringent safety precautions. Class A is considered to be the most stable, while stable rock represents the highest level of stability beyond typical soil classifications. However, the key distinction lies in the relative strength of Class B soils compared to the others, making them stable under proper conditions when managed correctly.