Spreadsheets work for a small team but break down quickly as the number of people, qualifications and sites grows, since nobody can see at a glance who is expiring soon or who is qualified for a given job. Updates also depend on one or two people keeping the file current.
Moving to a system starts with cleaning up the spreadsheet, agreeing on a standard list of qualifications and importing the records. Once that is done, the system can handle expiry reminders and qualification checks during job assignment, which is where the spreadsheet usually falls short.