Inspections of natural gas and biogas pipelines

A natural gas pipeline requiring a construction permit must undergo a commissioning inspection before being put into operation, followed by periodic inspections every eight years. Generally, the installation company or contractor orders the commissioning inspection for the natural gas pipeline, while the operator is responsible for the periodic inspections.

Natural gas pipelines are classified based on their intended use into transmission pipelines, distribution pipelines, and service pipelines. Transmission and distribution pipelines always require a construction permit. A construction permit is required for service pipelines when the facility’s fuel capacity is at least 1.2 MW. A construction permit is not required for service pipelines if the fuel capacity is below 1.2 MW and the maximum allowable operating pressure of the pipeline is up to 0.5 bar or if the nominal size of the pipeline is up to DN 25. A regional construction permit may also be issued, allowing the construction of distribution pipelines and associated service pipelines for facilities with fuel capacities below 6 MW and operating pressures below 8 bar.

Commissioning Inspection

The commissioning inspection verifies that the natural gas pipeline complies with current regulations and the conditions set in the construction permit. It assesses the pipeline’s placement, structure, and readiness for use. The commissioning inspection should be conducted during construction so that the natural gas pipeline can be thoroughly inspected either all at once or in several parts.

Periodic Inspections

For a natural gas pipeline that required a commissioning inspection, a periodic inspection must also be performed every eight years. During the periodic inspection of the natural gas pipeline, it is checked that the pipeline has been maintained in accordance with current regulations and that the pipeline and its associated equipment and structures are in operational condition.

Flexible Service

Insteam Oy is an inspection body approved and monitored by the Safety and Chemicals Agency, authorized to carry out commissioning and periodic inspections of natural gas pipelines. We conduct inspections expertly and flexibly according to the customer’s schedule.