At least in 13 petrol bunks owned by Telangana Police Jails Department, the rule of 'No helmet, no petrol,' is being strictly implemented. Two-wheeler drivers, who are coming for petrol without wearing helmets, to these bunks that are situated all over the state, are returning empty-handed. This is causing a loss of 10 per cent of the revenue to the Jails Department. Nevertheless, the rule is being implemented as a social cause from July 23rd onwards, Director General (DG) of Jails, V.P.Singh said.