What does 'sufficient experience' mean?

In order to qualify as a professional ergonomist, an applicant must demonstrate a minimum of 3 years' full time qualifying work experience in the practice of ergonomics/human factors, and/or teaching, and/or relevant research.

Experience gained without a degree from a 'Qualifying Course' counts at a rate of 75%. In other words an applicant without a qualifying degree (e.g. an Associate Member) has to demonstrate at least 4 years' suitable experience. All work experience gained by graduate applicants following the award of their qualifying degree counts in full.

So in summary, if you have a qualifying degree then you need a minimum of 3 years’ work experience as an ergonomist, if you don't have such a degree, then you need 4 years’ work experience.