I am unsure of the difference between a PCBU and an officer under the WHS Act. Our company structure includes directors, an executive committee, managers and workers. Who are the PCBUs and who are the officers? Is it possible to be both at the same time?
A person conducting a business or undertaking (PCBU) is the entity that operates the business. In your case, it would most likely be the incorporated company.
Officers of the PCBU are the people who have significant control over the business or who can contribute substantially to the decision-making process. This includes the directors, the executive committee and most likely the managers who exercise substantial control over part of the PCBU. For example, an operations manager of one site in a two-site business where his or her site represents 85% of production would be an officer.