Inconsistent readings have been detected at a monitoring station within the Port Hedland Ambient Air Quality Monitoring Network.

The Port Hedland Industries Council has launched an investigation to determine the nature of the discrepancy in PM10 readings, at the Taplin Street monitor.

The Regulator – the Department of Water and Environmental Regulation (DWER) – has been advised and will continue to be updated as the investigation progresses.

PHIC chief executive Kirsty Danby gave a full briefing to the Community Industry Forum at a meeting in February in which she explained the steps taken initially to check the Network, and details of the investigation.

Forum members visited the Taplin Street monitoring site accompanied by air quality experts responsible for operating the Network.

The forum agreed with PHIC’s approach to investigate the reasons for the inconsistent readings.

The forum and other interested stakeholders will be kept up to date as information becomes available.

The inconsistent readings were detected after PHIC requested a series of additional checks to be conducted on the PM10 monitoring equipment at Taplin Street.

Inconsistent readings were confirmed on 23 January 2020.

The Network is maintained and operated by Ecotech, a specialist in air quality monitoring, which is responsible for site equipment calibration, data storage and data validation.

PHIC fully funds the costs of this service and makes the results of monitoring publicly available in real-time.

As part of this service PHIC requires Ecotech to routinely check and calibrate all PHIC monitoring stations every two months, which exceeds Australian Standards requirements.

Ecotech Chief Executive Nicholas Dal Sasso said its specialists have examined the instrumentation but were unable to find a cause for the inconsistent readings. The instrument has been sent to the manufacturers in the United States for further examination.

“All PHIC monitoring stations are checked and calibrated every two months, which is above Australian Standards as requested by PHIC,” Mr Dal Sasso said.

PHIC Chief Executive Kirsty Danby said everything necessary would be done to understand the reason for the inconsistent readings and ensure the integrity of the Network data, including investigating running parallel monitors across all sites.

“Additional measures to ensure accuracy of results from every station in the Network will be implemented as part of PHIC’s commitment to accurate reporting,” Kirsty said.

“PHIC is committed to open and transparent communications with the Port Hedland community. As PHIC will continue to make the monitoring data available to port users and publicly via our website, it is important the data is credible and trusted by all parties.”

Replacement monitoring equipment was installed at Taplin Street and has been delivering consistent datasets since 15 January 2020.