Under the award and our EBA, you should never and legally do not have to work in the rain. However, you must make the work area safe before you cease work. If a concrete pour has commenced prior to it raining, the pour can continue until finished, but all affected workers must be provided with wet weather gear and shall be paid double time until they have completed their work. They are then allowed to go home for the remainder of the day without any loss of pay.
If it rains at/before starting time and there are no covered walkways from the amenities to the workplace, workers do not have to go to work unless the rain stops or a covered walkway is provided.
Further information can be found in the Construction and General Award (Clause 23)
If you're still unsure, you can Contact Us
CFMEU EBAs state that workers will stop work and leave site when the temperature reaches 35 degrees. The temperature is measured at the nearest Bureau of Meteorology weather station to the work site.
A printable version of this heat policy which includes starategies for working in hot weather that's below the 35 degree cutoff can be found here.
If there is a Shop Steward or Health and Safety Rep who works on your site, you should let them know first. If not, then there are still lots of ways you can work this out. If you're a union member and there's nobody in your workplace that you feel comfortable reporting it to, you can call our office on (08) 8231 5532 and speak with an Organiser. Safe work SA are the government regulator in South Australia (link to Safework SA) https://www.safework.sa.gov.au/