Accurate flow measurement drives commercial value, regulatory assurance, and operational integrity across the energy sector. A flow measurement audit provides a structured, independent assessment of metering systems to determine whether they are performing within expected standards, operating limits and contractual or regulatory requirements.
At SOLV®, we deliver audits as a UKAS accredited ISO/IEC 17020:2012 Type A Inspection Body (No. 28833). This accreditation provides assurance of impartiality, technical competence, and adherence to internationally recognised inspection principles. Some oil and gas operators require ISO/IEC 17020 accredited audits as part of regulatory obligations, contractual agreements, or internal quality management systems, particularly in high-value custody transfer or joint-venture contexts.
What Does a Flow Measurement Audit Involve?
A flow measurement audit typically involves reviewing instrumentation, control systems, procedures, calibration records, and data integrity across the full measurement chain. The purpose is to identify any non-compliance, risk of mismeasurement, or opportunities for improvement.
Audits may be required periodically, during system upgrades, following significant events, or ahead of regulatory inspections. The scope can range from individual instrument reviews to full metering system evaluations.
How is a Flow Measurement Audit carried out?
A flow measurement audit involves a structured review of metering system components, procedures, and records against clearly defined audit criteria. These criteria are established in advance and may include internal procedures, contractual requirements, regulatory expectations, and industry standards such as the Energy Institute’s HM60: Guidelines for the Management of Measurement Systems (2019). SOLV® works with each client to agree the relevant criteria to ensure the audit is focused and appropriate to the system context.
If you’d like to learn more about how audit criteria are selected and why they matter, you can read our earlier article: Why Use Audit Criteria?
During the audit, each inspection item is evaluated against the agreed criteria. Findings are then assigned a compliance category to reflect their severity and impact:
Category 1: Non-compliant with a confirmed mismeasurement (e.g. temperature error causing volume bias)
Category 2: Non-compliant with potential for mismeasurement (e.g. meter not proved for an extended period)
Category 3: Non-compliant, but no impact on measurement (e.g. missing calibration certificate)
Comment: Neutral or contextual point, such as access limitations or examples of good practice
Categories 1, 2, and 3 require corrective action to achieve compliance. Comments are advisory and intended to provide useful context, highlight constraints, or identify opportunities for improvement.
This categorisation helps operators prioritise actions, manage risk, and continuously improve measurement performance.
Why Use an ISO/IEC 17020 Accredited Inspection Body?
ISO/IEC 17020 sets the international benchmark for inspection bodies. Using an accredited provider ensures that audits are:
· Independent and impartial
· Conducted by technically competent staff
· Delivered under a quality-assured system
· Recognised by clients, regulators, and joint-venture partners
At SOLV®, we undergo regular UKAS Accredited Audits to maintain our accreditation and continually improve our processes. Whether you need a full system audit, a pre-inspection review, or third-party verification, we’re here to support you, please get in touch.