I had to submit a cover letter and cv only, I was then invited to the assessment day. The assessment day was really good, really friendly environment. It consisted of: -SJT quiz - a friendly group activity (we assigned roles as a team) and worked to construct a bridge. - a tour of the site - generic competency interview -interview with the team leader (similar to the competency interview) -technical interview, we were given a process diagram of a HX system and asked questions about it