How often do dangerous goods drivers in Lianyungang make-up exams?

February to March. Dangerous goods driver qualification certificate, according to the national "road transport practitioners management regulations" to hold an exam every quarter, that is, in February-March, an exam will be organized to make up the exam. Persons who have applied for the qualification certificate of transport drivers of highly toxic chemicals and explosives, and passed the corresponding examination and assessment, and obtained the corresponding qualification certificate.