Eight companies, including one owned by the richest man in Australia, will be prosecuted in connection with two deaths during Cyclone George, WA's safety watchdog says.

Cyclone George killed three people when it ripped through WA's Pilbara region with winds of up to 275 kilometres an hour in March, 2007.

Queensland man Craig Allan Raabe died from severe head injuries and Perth mother of two Debra Till, 47, died when the storm flattened a Fortescue Metals Group construction camp, owned by billionaire Andrew Forrest.

Nearly 30 people were airlifited from the camp a day after the category four cyclone smashed FMG's rail camp 1, sending temporary accommodation buildings flying.

A 74-year-old man died of a suspected heart attack at a nearby station during the cyclone.

WorkSafe WA said it would prosecute eight companies in relation to the two deaths at the FMG camp and injuries to seven people during the cyclone.

FMG, Spotless P&F Pty Ltd, The Pilbara Infrastructure Pty Ltd, BGC Contracting, Laing O'Rourke Pty Ltd, NT Link, WorleyParsons Services and Spotless Services Australia face a total of 49 charges under the Occupational Safety and Health Act.

The charges include failing to provide and maintain a safe working environment, failure to maintain employer provided accomodation and constructing and designing temporary structures and failing to ensure they could withstand cyclones.

WorkSafe commissioner Nina Lynhe said the large number of charges brought against a number of entities demonstrated the breadth of occupational safety and health responsiblities.

"The finalisation of charges was an important step in an intensive process that had taken place over the past 16 months," Ms Lynhe said.

"The investigation into the tragic deaths during Cyclone George was a significant and complex one involving extensive WorkSafe resources," she said.

"It is now a matter for the courts to determine."

All eight companies will appear in the Perth Magistrates Court in September.

Source: WAToday