CAA set their own SMS and audit standard based on ICAO's, there is a really good A3 page of how it aligns with an OHSMS. https://www.caa.govt.nz/Advisory_Circulars/AC100-1.pdf - Chris, this link will take you to part 100 - SMS.

In a previous role I was involved in the development of a SMS for an aviation business, and the SMS referred to 'aviation and workplace safety and health', we refused to have 2 SMS's, one for aviation and one for workplace. It took a while for them to understand that what they were trying to get us to do, we were already doing, and understand that they way you manage workplace safety (and health) and aviation safety is exactly the same.