Has there been an increase in the number of criminal records checks for engineers in recent years? Factor out jobs which require working with children or vulnerable adults, or those requiring certain types of security clearance.
For those who are not sure if their historical convictions are spent, and therefore if they need or need not be mentioned on job applications not requiring a DBS or security clearance
For those who are not sure if their historical convictions are spent, and therefore if they need or need not be mentioned on job applications not requiring a DBS or security clearance