Una: The Una district administration on Saturday issued revised timings for all schools owing to the dense fog and excessive cold conditions here.Classes at all schools -- primary, middle and secondary -- both government and private, will be held from 10 am to 3 pm from January 22-31, according to the order issued by Deputy Commissioner Raghav Sharma.Regular classes were earlier being held here from 10 am to 4 pm.The Una DC said that in view of the safety of school children amid the continuing extreme cold in this district, the administration has decided to revise the school timings after the recommendation of the Deputy Director of Directorate of Higher Education.He added that that the reduced duration will be compensated by eliminating the prayer meeting and lunch break time.The Una district has been witnessing dense fog for the past few days. The minimum temperature here on Saturday morning was noted at 5 degrees Celsius, according to weather bulletin.According to the local weather department, dense fog is likely to continue in isolated areas of the lower hills and plains of the state till January 22.