ビルメン4点セットの難易度について【資格】

4-Piece Building Maintenance Kit Class 3 Refrigeration Machinery Supervisor Class 2 Electrician Class 2 Boiler Technician Class 4 Hazardous Materials Certification Let's talk about which certifications are the most difficult. 0:00 4-Piece Building Maintenance Kit 1:09 Hazardous Materials Certification Class 4 1:44 Class 2 Boiler Certification 2:31 Class 2 Electrician Certification 3:23 Class 3 Refrigeration Machinery Certification #BuildingMaintenance #Qualifications