In general, the HSWA regards the health and safety of all people working at a place or site to be the responsibility of the primary PCBU of that site. This means there should be no distinction between staff, visitors or a person visiting that site for the purposes of their business; be they a cleaner, a plumber, or a computer system support technician. Their health and safety on this site is your responsibility.
In the HSWA, it is specifically noted that PCBUs are required to take all reasonably practicable steps to ensure the safety of all non-company people, while on site.
This section sets out the procedures which need to be completed by a PCBU, to ensure compliance with the above Act and Standard. Remember that there is no point in having a contractor sign the Contractor’s Acknowledgement if you are not going to then induct them correctly onto the site and regularly monitor and evaluate whether they have complied with the agreement that you have both signed.