New legislation comes into effect on 14 May 2018 requiring all workers performing work for reward in domestic premises to turn off all sources of electricity at the main switchboard before entering the premise roof space. This requirement applies to all types of work, not only electrical.
Two electrical workers died in roof spaces of domestic dwellings in Western Australia between 2013 and 2016. The Report of the Royal Commission into the Home Insulation Program (HIP) also highlighted that three of the four fatalities involved in the installation of insulation under the HIP was caused by electrocution, which could have been avoided had the main switch been turned off prior to entry.
Under the definitions in the legislation, applicable buildings include most types of residential property including small hostels and boarding houses as well as private garages and sheds. It also includes applicable building class types which have been repurposed, such as houses converted into business premises such as medical practices or retail outlets.
A guidance note has been issued by the Commission for Occupational Safety and Health detailing what the legislation says and the details of the new working in roof space requirements. You can access that guidance note at https://www.commerce.wa.gov.au/publications/guidance-note-working-roof-spaces