If our policy says, ‘You must tell us if you have an infectious disease so that we can take steps to protect other workers and our clients’ and a worker has HIV or hepatitis, does the worker have a right to keep such a condition to themselves and let their employer rely on universal precautions for protection of other workers and clients?
There is no general right of privacy in Australian law, so the answer to your question is no, the worker does not have a legal right to refuse to provide the information.
From a practical point of view, though, a worker might simply refuse to provide the information or in fact provide false information.
In order to limit a worker’s concerns regarding the request for personal information and remove any confusion in the process, it is critical that the purpose for collecting the personal information is made clear to workers and that it is for a legitimate purpose.
It should be made clear that the information is only going to be used for the particular purpose you have outlined in the policy and that there will be protection against improper access and disclosure of personal information. Steps should be taken to ensure that protection of privacy actually does occur.