COR (Certificate of Recognition)

A contractor management platform used by operators to verify that subcontractors meet safety, insurance, and compliance requirements before being allowed to work on sites. Maintaining ISNetworld compliance is essential for subcontractors working with major operators.

The complete package of equipment, personnel, and services required to drill a well, which determines the scope of work subcontractors are hired into — whether supplying a single service line or multiple integrated components across the operation.

The construction and assembly of the above-water structures on offshore platforms, including decks, modules, and processing equipment, where subcontractors are typically engaged for specialised trades such as structural welding, pipefitting, electrical, and instrumentation work. For field service companies, topside scopes often involve strict offshore safety certifications, remote logistics, and milestone-based billing tied to fabrication progress.

A company hired by a general contractor or directly by an operator to perform a specific portion of work. Subcontractors often specialize in particular services or trades.

The initial release of fluids, sand, and gases from a wellbore after hydraulic fracturing, which requires specialised crews and equipment on-site to manage, separate, and dispose of the returned materials safely. For field service subcontractors, flowback operations represent a distinct scope of work with dedicated mobilisation requirements and often involve tight scheduling windows tied to the operator's completion timeline.

The phase of oil and gas well development after drilling is finished, encompassing the work required to prepare a well for production — including perforating, fracturing, and installing wellhead equipment. For subcontractors, completions represent a concentrated burst of high-demand field work where specialised crews, equipment, and services are mobilised under tight timelines.