After obtaining a certificate of professional competence, insulation installers are registered in the Certificates of Professional Competence Register This certificates register can be consulted by (potential) clients to check if your insulation installers have the required certificates. Employers and employees can also consult this register to check the validity period of their certificates. Because a certificate of professional competence is valid for five years, an employee must prove every five years that he or she still has the required professional competence. In this way, you guarantee the professional competence of employees now and in the future. Click here to access the certificates register.