All Bihar government departmentswill start functioning from April 20, a General Administration Department (GAD) order said.All government officers of Group A and B will be present in the office on all working days while 33 per cent of Group C employees and those on contract will be present in the office of their total strength, the GAD order said.All officers and government employees will have to follow the national guideline issued to contain COVID-19. Besides, officers and employees will have to wear masks, use sanitizer and practice social distancing in the office, the order said.All employees, data entry operators, employees on contract, office attendants, assistants, stenographers posted in different sections/cells will work as per roster of the department, it said.The Education department has also issued a separate order to open all its offices and concerned directorate and subordinate offices from April 20.A Home department order said not more than five employees will gather at a particular place in the office. Chewing pan, gutkha, tobacco and spitting in the office premises will be considered as a punishable offence, it said, adding that offices will be sanitized.