A jumping castle at the centre of the Hillcrest Primary School tragedy wasn't secured at all points, and the operator failed to provide workers with instructions and training, it is alleged.
Six children died and three were badly injured when a wind gust lifted the castle into the air during end-of-year celebrations on December 16, 2021.
The operator of the castle, a company called Taz-Zorb run by Rosemary Anne Gamble, was charged in November with failing to comply with health and safety duties.
Tasmania's Director of Public Prosecutions (DPP) alleges the castle was tethered at four of its eight anchorage points.
It is also alleged pegs were not installed at the recommended 45-degree angle and pegs recommended by the manufacturer, or a suitable alternative, weren't used.
According to court documents, seven students were on the castle when a "significant" weather event occurred, causing it to become dislodged and airborne.
They fell from the castle, while a blower attached to the castle to keep it inflated struck a nearby student.
It is alleged Gamble failed to ensure the anchorage system was sufficient to prevent the castle from lifting and failed to ensure there was a peg at each anchor point in line with the manufacturer's instructions.
She has not entered a plea to the charge under the Work and Safety Act and is expected to appear in Devonport Magistrates Court on February 2.
It is alleged a continuous wind monitoring device wasn't used, despite the company using one in the past and it being available commercially.
Gamble arrived at the school with two workers, and set up the castle and zorb balls.
It is alleged she failed to provide the workers with information, including the manufacturer's operating manual for the castle.
The DPP claims there was a failure to provide workers with training and instructions in accordance with the operating manual, including the requirement to use each anchorage point.
Workers were also inadequately supervised during the castle set-up, it is alleged.
It is claimed the manufacturer's instructions were available to be downloaded and clearly stated all anchorage points needed to be used.
There were enough pegs available for each anchorage point and suitable alternatives, in the form of star pickets, were also on site.
It is alleged the failures exposed individuals to the risk of serious injury or death.
An outpouring of community support followed the deaths of Chace Harrison, Jalailah Jayne-Maree Jones, Zane Mellor, Addison Stewart, Jye Sheehan and Peter Dodt.
Preparations for a coronial inquest have been put on hold because of the health and safety charges.
