Upstream

A standardised unit of energy measurement that converts different types of oil and gas production into equivalent barrels of crude oil, used by operators to report total production volumes when determining project scope and service requirements for subcontractors.

A ship-shaped offshore vessel that processes and stores crude oil or gas directly at sea, then transfers it to tankers — for subcontractors, FPSOs represent remote, long-duration worksites with strict offshore safety certification requirements, specialised crew rotation logistics, and scope that can span topside maintenance, marine systems, and instrumentation work simultaneously.

Steel pipe installed in a wellbore to provide structural integrity and prevent contamination between different geological formations, requiring specialized installation and cementing services that subcontractors frequently provide during drilling operations.

A document created in the field that records work performed, equipment used, materials consumed, and time spent. Field tickets are the basis for invoicing and must typically be approved by the customer before payment.

An unmanned, tethered underwater robot used to inspect, survey, or perform work on subsea pipelines, wellheads, and structures — subcontractors providing ROV services typically require specialised operators and vessels, and should account for mobilisation costs and standby rates when bidding these scopes.

A project delivery model where one main contractor handles all phases from design to completion, typically creating multiple subcontracting opportunities for field service companies across different project phases. For subcontractors, EPC projects often mean working under a prime contractor who coordinates all trades and manages the overall timeline and specifications.