TVD (True Vertical Depth)

A budgeting document used in oil and gas projects that outlines expected costs and seeks approval before work begins. Subcontractors often work under AFEs issued by operators.

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.

Operations performed on an existing well to restore, maintain, or improve production. Includes activities like recompletions, artificial lift installation, and remedial cementing.

The number of drilling rigs actively operating in a region. Published weekly by Baker Hughes, the rig count is a leading indicator of activity levels in the oil and gas industry.

A series of controlled flow and pressure measurements performed on a newly drilled or existing well to evaluate its production potential and reservoir characteristics; for subcontractors, this work often involves deploying and operating specialised equipment such as separators, flowback units, and data acquisition systems under tightly scheduled, high-priority conditions.

Refers to offshore oil and gas operations conducted in water depths exceeding 300 metres, where subcontractors and field service crews must hold specialised certifications, work within stricter regulatory frameworks, and often face extended mobilisation timelines and higher equipment day-rates.