An in-line inspection of the hydrogen pipeline was being conducted and prior to the last run of the in-line inspection tool (mfl), hydrogen gas was released and ignited from a blind flange connection failure on a temporary separator filter installed at the receiver site. The fire was immediately identified by on-site personnel. There were no injuries. The pipeline section was isolated and de-pressurised to the facility flare. Local emergency responders were dispatched and contained and extinguished the fire. The fire affected the station piping and equipment in the surrounding area.

Early in the morning of (3:00 AM), the personnel on one of the companies on site reported a potential pipeline leak just south of the valve station. The potential leak was discovered due to bubbling water in the ditch. No visible hydrocarbon sheen was noted, indicating a probable non-hydrocarbon gas leak. Later in the morning, the personnel tested their area gas pipelines and determined that their company was not the source of the leak. Later on the same day, another company tested their pipelines and determined that their hydrogen pipeline was the source of the leak.

At 17:30 on 5 may 2019, the pipeline operator was notified by a third party that there was a possible leak on its hydrogen pipeline, as identified by sound. Operator personnel arrived on the site at 18:30 and confirmed that hydrogen was present in the area. The location was in an isolated area. Manual isolation valves were shut to close in the segment and it was manually blown down. At 08:52 on of the day after the operator determined that the incident met reportable criteria and called the national response centre at 09:22.

Release from a welding of a hydrogen transmission pipeline At 12:45 pm the operation control centre (OCC) recognised that a customer flow and pressure dropped significantly. At 13:28 the OCC made the decision to close the upstream remote operated valve. At 15:00 the pipeline technician arrived on site and confirmed the breach in the pipeline. Additional pipeline operations technicians were deployed to isolate both manual block valve upstream and downstream of the incident site.

A hydrogen release and subsequent fire occurred at meter station of a pipeline transporting hydrogen to a refinery. Local refinery emergency response team responded and secured the area. The pipeline was isolated, and the fire extinguished itself. During a winter storm, the area was experiencing abnormal freezing conditions and widespread power outages were occurring. As a result, third party hydrogen supply to the refinery was reduced. These upsets resulted in the need to export larger than normal flow rates on the hydrogen pipeline.