OSHA Soil Types

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Do you wish to ensure the ultimate security of your employees at the construction site? In typical cases, the construction employer is required to classify the type of soil as per the OSHA Soil Classification. This process must be carried out prior to the selection of the manufacturer shoring or open-cut sloping for the given project. The specific OSHA Appendix is known for classifying the soils into different categories on the basis of stability –Type A soil, Type B soil, and Type C soil. If you have been working with excavation shoring systems and have received the competent training class services, must be able to recognize the given terms. In this post, we will help you in understanding the basic terms related to OSHA soil types for the overall efficiency of the excavation work.

There are 3 Main OSHA Soil Types

The soils can be classified and sorted depending on several characteristics including fertility, strength, color, chemical compositions, weight, permeability, and organization.

  • Type A OSHA soil type refers to the cohesive soil types having the compressed, unconfined strength of around 1.5 tsf (ton per square foot) or 144 kPa.
  • Type B OSHA soil type is referred to as the cohesive soil type having the unconfined compressive strength of over 48 kPa or 0.5 tsf, but should be less than 144 kPa or 1.5 tsf. In other words, this type of OSHA soil is granular cohesionless soil that has angular gravel, sandy loam, silt loam, silt, and even silty clay or sandy clay loam in some cases.
  • OSHA soil type C soil implies cohesive soil that has an unconfined compressive strength of around 0.5 tsf or less. Alternatively, it can be referred to as the granular soil type including variations like loamy, sandy, or clay. Type C soils are also submerged soils or soil types that have been water as freely seeping through them.

The overall stability of the cohesive OSHA soils is based on electrical and chemical bonding. At the same time, the stability of the non-cohesive soils depends on the overall friction. Water is known to decrease the stability of both cohesive as well as non-cohesive soils. While determining the overall efficiency of the soil at the construction or excavation site, it is important for the contractors to analyze the OSHA soil type effectively. This helps in ensuring the safety of the employees during excavation work.