Applies to drilling or redrilling oil or gas wells and includes erection or dismantling of drilling rigs, formation fracturing, cementing and installation of casing when such operations are performed by the employees of the drilling company. Contemplates cleaning or swabbing of a new well that has not been completed, risks that own and lease to drilling contractors special drilling, baling, fishing or casing-cutting tools with complete operating crews and drilling of oil and gas wells for Fire Flooding, Thermal Flooding and Water Flooding. Refer to code 6213 for risks leasing specialty drilling tools with supervisory employees.