KOCHI: Despite a green light by the Central government to conduct classroom training for airline and airport staff on safe carriage of dangerous goods and radioactive materials on aircraft, the police have denied permission to Kochi-based Speedwings to hold the classes citing that the state government has prohibited such training. In a circular issued on August 11, DGCA, the civil aviation regulator, allowed re-opening of Dangerous Goods Regulations (DGR) training classes from August 17.