South Australia's workplace inspector has laid criminal charges against the state's police and infrastructure departments over the death of a woman in a freezer.

Debra Summers, 54, was employed by SA Police as a cook and a cleaner when she was found dead in a freezer at the Echunga police training reserve on October 4, 2016.

SafeWork SA executive director Martyn Campbell said she died of hypothermia and the lock on the freezer had not worked properly.

Following a lengthy investigation, criminal charges were laid on Friday against Ms Summers' employer SA Police and the Department of Planning, Transport and Infrastructure, which is responsible for maintaining government sites.

"South Australia Police had a duty of health and safety and failed to comply with that duty," Mr Campbell said.

"There were a number of failures that led to the tragic death of Ms Summers."

He said the maximum fine applicable to SA Police under the state's health and safety law was $1.5 million.

The case will come before the South Australian Employment Tribunal on November 21.

Treasurer Rob Lucas said his thoughts were with Ms Summers' family.

"The Government respects the independence of the regulator and, as this matter is now before the courts, it would be inappropriate for me to provide further comment," Mr Lucas said.

Ms Summers died of hypothermia after getting stuck in a police freezer in 2016. ( ABC News )

Warning about cold rooms and freezers

Following Ms Summers' death, SafeWork SA issued a safety alert about safety management to prevent injuries and death when working with cold rooms and freezers.

The alert stated that employers and businesses were responsible for ensuring cold rooms were in good working order, with emergency alarm buttons fitted and regularly tested.

Mr Campbell reiterated on Friday the importance of businesses and employers maintaining their workplaces, acknowledging that "lone worker" policies were always difficult to manage.

In May, the Independent Commission Against Corruption (ICAC) launched an evaluation of SafeWork SA, looking at its practices, policies and procedures, amid concerns about the risk of corruption, misconduct and maladministration.

Submissions for the ICAC evaluation closed last Friday.