If you notice a flurry of activity at Bombo Headland tomorrow, don't think the worst.

A multi-service emergency simulation training day, involving more than 100 coordinators and participants, is being held then (16 November), to help prepare for a number of eventualities.

Hosted by Illawarra Shoalhaven Local Health District (ISLHD), the training day provides colleagues across the health system an opportunity to work together in a different and challenging environment.

NSW Ambulance, NSW Ambulance Medical Retrieval Service, NSW Police Rescue and ISLHD Emergency Departments from Wollongong, Shellharbour, Shoalhaven and Milton Ulladulla hospitals will be participating.

They are set to test their skills in simulations of critically unwell patients including retrieval, triage, treatment and team interaction.

The exercise has been held in the past at Jerrara Dam and Killalea State Park where they ran scenarios ranging from adult and paediatric trauma, envenomation, burns and drowning.