Twenty days. It generally takes 20 days for Mianyang Construction Machinery Safety Association to obtain the loader operation certificate after passing the training of loader operation certificate and on-board operation certificate. Students can log on to the Professional Committee of Construction Machinery Vocational Education of China Construction Education Association (China Construction Machinery Vocational Education Network) for enquiries. Scan code query, this method is only applicable to the new certificate. Scan the QR code on the front of the certificate on WeChat, pay attention to the official account of WeChat and the national safety production examination, enter the official account of WeChat and click the scan code to query the certificate information.