First aiders should re-qualify every three years, otherwise:
the Health and Safety Executive (HSE) no longer considers them competent to act as a first aider they will not be counted towards the required number of first aiders in your workplace.
First aiders can re-qualify by completing a two-day first aid at work requalification course, but if some time has passed since the certificate expired, the HSE recommends completing the three-day first aid at work course.
We support the HSE recommendation that first aiders have annual refresher training to keep their skills up-to-date.