A report into a major chemical fire in Canberra last year has found that many automatic emergency calls were not made, because the systems in place did not have sufficient capacity.

It’s not often that any emergency service gets to conduct a real-life test of a system in a genuine emergency that ends with no loss of life and no widespread property damage – but that’s what happened last year when a waste facility operated by Energy Services Invironment [sic] caught fire in September last year.

The fire burned a recycling plant for transformer oil in the Canberra suburb of Mitchell, and in bringing the fire under control, a 300-meter exclusion zone was declared, and a number of suburbs in the path of the smoke were either evacuated or residents advised to stay indoors. All ACT public schools north of Lake Burley Griffin were closed on September 16 in response to the risk of exposure to toxic smoke.

The ACT directorate of Justice and Community Safety has now released documents under freedom of information relating to the incident, here.

Its investigation into the response to the fire has found that while at a small scale the practice of sending SMSs to mobiles and automatic phone calls to fixed lines worked well, at a larger scale, the system didn’t cope. In particular, the automatic recorded calls to fixed lines ran into trouble.

The system coped with the first campaign starting at 1.38 am, which targeted just over 22,500 fixed lines with an evacuation message: all numbers were dialed, although a large number turned out to be invalid.

However, the second campaign, which started at 3.19, didn’t perform so well. Of the nearly 87,000 numbers targeted with a “stay indoors” message, 80 percent were never dialed.

Some of the problem appears to be the capacity of the Telstra exchanges involved: the report states that splitting target regions into smaller areas offer a better prospect of success, but notes that “this may not assist where the system is accessing a single telephone exchange to deliver the messages”.

The design of the system the emergency operator was using is also an issue, with the report stating that although the second campaign was too large to be delivered within the 30 minutes stipulated by the operator, the system didn’t advise that it would take more than six hours to complete.

“While the system does identify the necessary time duration to complete a campaign, the system does not provide a warning to the operator that the proposed campaign is too short,” the report states. Telstra has recently signed a contract to provide a national system of emergency notification. The Register has contacted Telstra for comment on the report. ®