Churches have legal obligations to provide first aid facilities and sufficient staff trained in first aid.
A rough guideline would be to have one trained first aider for every 50 participants, with a minimum of one per ministry or event.
For example- if 200 people attend your Sunday worship service, you should ensure four (4) first aiders are present and available.
A suitable first aid kit should be available, where ever your church ministry takes place. Such as the church office, sanctuary, car driving to youth event, camp site, or a private home where Bible study takes place.
Ensure everyone knows who the first aiders are, and, where to find the first aid kits.
Here is a sample poster:
If there is any injury or ‘near miss’, an incident or injury form should be completed.
For detailed advice, including regarding first aid kits and first aid training, see this resource from Safe Work Australia