The Vocational Education and Training (VET) system of qualifications & national units of competency as well Safework High Risk Work Licences ensure that operators and workers are trained to the standard required for each Nationally accredited unit of Competency. However, the VET system is only able to guarantee that an operator or worker is competent at the time they were assessed. Over time their competency may decline. Reassessment may also be an insurance requirement to ensure current records of competency are maintained.