The Traffic Signs Regulations and General Directions (TSRGD) 2002 permits the use of certain regulatory signs (other than speed limits) on one side of the road only at a junction if the carriageway (rather than the whole road) is less than 5 metres wide and the sign is so placed that its centre is within 2 metres of the edge of the carriageway. The signs to which this relaxation applies include �No entry signs� and entry signs for controlled parking zones and pedestrian zones.