ACT Chief Coroner Lorraine Walker recently handed down her findings into the death of 51-year-old Shane Robert Senini.

Mr Senini died on August 2 last year after an explosion outside St Clare of Assisi Primary School in Conder. He was at the school to pick up his son from after school care.

His death was investigated by the coroner due to his death being directly attributable to an accident.

Ms Walker declined to make any recommendations about public safety in the wake of Mr Senini's death.

Other parents who had parked in the school car park reported hearing a bang and one woman said she felt her car shudder.

One man said he felt an explosion followed by quiet before he heard a strange whistling noise. He looked up and saw a ladder flying through the air, debris was scattered all around Mr Senini's ute.

The parents and the school's assistant principal performed CPR on Mr Senini, who they found lying on the ground near the exploded ute. The applied a defibrillator and rendered first aid until firefighters arrived.

Mr Senini was transported to the Canberra Hospital where he later died from his injuries.

Professor Johan Duflou conducted a post-mortem examination of Mr Senini and determined he died of severe chest and head injuries and facial fractures deemed "not usually survivable". There were no drugs or intoxicating substances found in his body.

There was evidence before Ms Walker about Mr Senini's struggles with anxiety and a previous suicide attempt which he decided not to follow through with.

Ms Walker said she had considered whether Mr Senini's death could have been a result of intentional self-harm and she was satisfied it was not.

There was evidence Mr Senini was in a positive mental state on the day of his death.

"I consider it unlikely that, if intending self-harm, he would have carried it out at his son's school and without leaving any indication of his intent," Ms Walker said.

"I find that Mr Senini died as the result of a tragic accident."

She determined he had inadvertently neglected to fully close the valve on an acetylene cylinder in the sealed storage unit of his ute.

Acetylene gas had leaked and built up in the storage compartment where it mixed with air and caused an explosive substance.

The multiple storage compartments in Mr Senini's ute's tray were connected to the vehicle's central locking.

A wire in the gas bottle compartment had worn over time and had become exposed, likely causing a short in the system when Mr Senini used his remote control to lock the vehicle creating a spark in the compartment.

The scene was examined by Fire and Rescue HAZMAT units, AFP forensics, the bomb squad, specialised gas technicians and WorkSafe ACT.

The Australian Standards in relation to the storage of acetylene gas cylinders requires them to be stored in a well ventilated area and fully closed. On the day in question Mr Senini did not store the gas bottles according to the standards.

Since Mr Senini's death WorkSafe ACT has released educational material regarding the safe storage of gas bottles.

After his death the school's principal, Matthew Egan-Richards, described Mr Senini as an active member of the school community who was well liked.

"He was a down-to-earth, good bloke [from a] lovely family [who are] very supportive of the school and very involved in their community," Mr Egan-Richards said.