To hold an IASI  licence, you must have a valid first aid qualification awarded by an accredited first aid provider. The course must be of a minimum of 2 days or 16 hours duration and for Level 2 and above must include an outdoor element.  For Level 1, the outdoor element is not a requirement but if you intend to progress to Level 2 you might wish to consider undertaking a suitable course from the start. 

Below is a list of suitable First Aid course providers:

World Class Training - First Aid for Outdoor Activity Snowsports

BASP First Aid - Specialising in the Outdoors

First Aid Events